A huge part of the reason why 32-bit is lasting as long as it does is because of corporate clients, not home users. Where I work, we have over 100,000 computers, all still running WinXP 32-bit. An announcement of an upgrade to Windows 7 over the summer said the upgrade will take several *years*. I expect us to be using Win 7 32-bit, as well, as we have a metric crapton of internal and contracted applications running and there's little need to upgrade hardware on all the machines. 

Microsoft needed to give the corporate side a good 32-bit platform to replace the aging XP, and Vista wouldn't have cut it. Win7 does, and it makes sense that Win8 will be 64-bit only, as that will give the corporate users more or less a decade or so to transition into using 64-bit machines. 

Was speaking of 32 bit OS version !!!

WinXP 32 bits have these 2gb application limit ( can be increased to 3 gb using tip and trick )...

The 32 bits Linux kernel 2.3.23, from 1999, have introduce the use of 64 gb ram...

The 32 bits MAC OS X 10.5 Leopard, from 2007, have introduce the use of max 32 gb ram...

Some old version of 32 bit windows support a lot of ram too : Windows 2000 32 bit datacenter with 32 gb ram, Windows server 2003 32 bit Enterprise with 64 gb ram, windows server 2003 32 bit datacenter with 128 gb ram, windows server 2008 32 bit Enterprise/datacenter with 64 gb ram...

Seem that if we remove all desktop 32 bit OS from Microsoft, all other 32 bit OS (  Windows, Linux, MAC ) are able to use at least 32 gb... 

The 2 gb limit only appear on the desktop version of windows 32 bits... it is not a hardware limit but a license limit... if a 32 bit windows version from 2000 was able to use more that 2gb, why it is not possible today...

Of course, if a gamer have more that 128 gb ram ( in some case, 64 gb ram ), the need to use x86-64 become a fact... to my knowledge, there is not yet desktop motherboard able to reach these limit... same my workstation motherboard have a limit of 96 gb...

So, what is the point to move from 32 bits OS to 64 bits OS when 32 bits OS can access a lot of memory... each time, the "2gb limit" is used like a excuse for push people to buy new OS... there is numerous good reason why it is interesting to use a x86-64 OS but the "2gb limit" is a false one...

Now, how does linux builds from 2002 (when winXP was released) compare to current operating systems in 2010?

Why do you wish compare a linux from 2002 to OS from 2010 ? If you wish compare something, compare Linux 2010 to other OS from 2010 !!!

By the way, these is a difference between "linux" and "linux distribution"... a linux distribution is a kernel + a desktop ( GUI )... windows is make of a kernel and a desktop too...

In the last 10 year, Microsoft have work more on the desktop ( GUI ) section that the kernel part ( who is the real OS )... on linux distro, you have a bunch of desktop ( gnome, KDE, Xfce, LXDE, etc )... kernel part of Linux evolve in function of the commercial release of new material or protocol...

At the kernel level, as today, Linux seem to be better... almost support all hardware, same old one ( not like windows )... support a lot of various disk operating system and processor... this happen due to the open source thing, not because linux dev are better... by example when you have the source of a old printer driver, it is easy to upgrade it or convert it to x64...

At the desktop level ( GUI )... it is all about taste and color... i like KDE but some like Gnome... there is GUI who make look a linux distro like a Win xp desktop, or a MAC desktop, or what you wish...

A lot of desktop thing introduce in Vista/win7 are in fact coming from Linux ( who itself is based on Unix )... lot of people have find the new right system ( administrator, user, etc ) to be a plague on recent win OS... well Linux/Unix user know this from long time... the aero desktop was introduce after the beryl/compiz 3d desktop was released on Linux...

At the software level, a lot of Linux software have make release for windows : Gimp, wings3D, OpenOffice, Firefox, etc...

As today, it is somehow difficult to compare Linux and Windows OS... both have their quality and default... due to the open source thing, Linux can become very powerful but only if you can compile software... same on my powerfull computer, it take several days of compilation for build linux from scratch... but final result is a kernel ( os ) build only for my material and who will use all the power... not really something for a Joe user

And that is your arbitrary choice.

Windows was available in 64bit since 2003.

My point was that you comparing windowsXP to current linux is like comparing 2002 build of linux to the latest from MS.

1. Those use a driver.

2. All of those had to be rewritten to work with vista 32bit anyways.

Your windows XP 32bit anti virus could not work on 32bit vista or 64bit vista without modification.

1. There is absolutely no risk.

2. You got it wrong, there is no reason to upgrade the OS for most of those cases... but if you DO upgrade the OS anyways there is every reason to go 64bit.

Strawman argument, memory is the least important feature of x86_64 architecture... It has a theoretical max speedup of 4-5x (very much depending on the app... 23% 7z compression speedup, 60% divx compression speedup, 0% h264 speedup, 400% hash caculation speed...)

Windows XP is from 2002, that is 8 yeras... decades old apps were NOT designed for windows XP.

And there is no "etc". The security apps (aka, "anti virus") is as simple as getting the 64bit version from your supplier... on the very VERY rare case that you use a driver based program (example, riva tuner) and there is no updated driver then you can't upgrade your OS period. Going from windows XP to windows vista requires a new driver, whether its 32bit vista or 64bit vista. You can NOT use 32bit windows XP driver in 32bit windows vista. (however, new drivers that were updated for vista32bit also include windows XP 32bit driver in the same package)

One could make a very compelling argument not to upgrade your OS period, just stay with XP instead of going to vista or win7 and save some bucks... but if you are already paying to upgrade, it costs you the exact same to go to 64bit win7 and you get better performance too and there is no extra risk cause any program that will not work on 64bit win7 will ALSO not work on 32bit win7.

Again, you're completely thinking from the average home consumer mindset. The corporate world is very different. Okay, let's say among the hundreds (literally) of unique executables we use here, there are no compatibility issues - and by the way, an app can work in 32-bit and not work in 64-bit that's not just a driver issue. And speaking of drivers, I'm assuming you realize that it's not uncommon for companies to upgrade all their devices very rarely? As a prime example, I'm typing on a 1gb RAM, 1.66 GHz company laptop. What about the couple thousand of printers we have mapped (and not the cheap inkjet ones either) just at this location alone? If their drivers don't work on 64-bit, who's going to rewrite them?

Your over-generalizing of the "safety" of upgrading a mass amount of computers effecting a mass amount of applications and devices would make any IT project manager tasked with the upgrade cringe

I've fixed systems that have 3 GB of RAM and running Windows XP 32 bit. No tricks were needed. XP saw all the RAM. As far as I know a 32 bit system can see 3.5 GB of RAM.

I was replying to taltamir, Thoumsin - it wasn't meant as a reply to your post.

On the issue of "Well, why not just keep XP 32-bit", because sooner or later (sooner) MS will just cut all support for it. Already only SP3 is supported, but once Win8 hits they'll probably stop supporting even SP3. I'm sure our upgrade people would love to stay on XP and save themselves the hassle, but it's a sinking ship, we'll have to upgrade even if we don't want to in order to keep up on security fixes if nothing else (hospital/patient data not quite a good thing to have compromised ).

People will still use XP even after MS quits supporting it. There are some out there that still use 98SE and 2000.

For example Fry's Electronics stores still use DOS.

Well support for XP SP3 and XP x64 SP3 will end in April 2014...

Vista mainstream support will end in April 2012...

Windows 7 in January 2015...

Only a few month difference between the end of support for XP and Windows 7...

For windows 8, take a look at http://www.winsupersite.com/win7/win8_leak.asp ... old news but it is the more recent leak !!!

Personaly, when my XP pro x64 become obsolete, i will simply use my Linux and/or Solaris OS... have windows now mainly for game... and since a lot of new PC game are only adaptation of console game, i will move on to a console in place of a new windows OS... or maybe only upgrade my laptop ( who is already using Vista x64 )

You are assuming that I am assuming...

I am saying that there is very good reasons for corporations not to upgrade AT ALL... that is, stick with winXP.

BUT, I am saying that IF the corporation is upgrading from winXP to win7, then they might as well make it 64bit win7.

The winXP to win7 transition is much more serious than the 32bit to 64bit transition.

The more people are on it, they more money they'll have to fix it!

Virtual Desktops will not run on Win7 home premium 64 bit ed.  Will it run on any other Win7 version?  Or just not at all on Win7?  Virtual Desktops is one of my favorite Stardock apps so would like to see it work on Win7.  Will it ever or is there something in Win7 which prevents that?