Actually, with the 64bit yes that is quite true, but like the other 64bit OS's out there, that is it's intended design...to utilize hardware resources beyond the 32bit hardware limitations. As for the 32bit version of Win7 vs WinXP SP3, I just finished a test...on an HP laptop 4GB RAM and Intel P8700 2.5Ghz dual core processor...Windows XP SP3 recognizes only 2.57GB of RAM and Win7 32bit recognizes 2.96GB as usable...after disabling all the eye candy and some fluff leaving all built in processes running...Win7 32bit is faster loading on login...and loading apps, especially the hogs like Outlook 2k7, IE8, Acrobat 8, etc...the full suite of Office 2k7 opened, with IE8 and Firefox 6 tabs each on different sites with at least 1 using a flash intro.
I might try it on a P4 system I have in my office...but it's a lot of work...Vista dogged it so if that's any indication, Win7 won't do any better.
That is mis-stated. The 32 bit version of the Windows OS has to allow the space requested by drivers, and ROMS. That space is private. The reduction in address space is not under Microsoft's control. It is the drivers and other physical address requirements of the hardware that cause the reduction of user addressable memory.
In a laptop, it is all over the place as the video driver will merrily steal away any amount of RAM it wants.
Try running a video application in 2GB of RAM on Windows 7 versus XP then come back and tell me which is faster. That was my whole point, specifically. I can do in 2GB of RAM what requires 4GB of RAM with Windows 7 or Vista. The 32bit version of Windows 7 does not allow a user to access all 4GB or RAM. It will depend on the video card RAM more than anything else.
You ever try running Windows 7 (32 bit) in 2GB of RAM and actually try to get any work done? Chug, chug, chug.
For me to run Windows 7, I would have to buy 4GB of RAM and the operating system. All for the pleasure of not gaining anything at all. On what planet does that make any sense?