Here's a quote from PC Magazine on Vista beta:
"The most significant element of Microsoft's performance story is that 32-bit and 64-bit versions of Windows Vista are being built concurrently, so that users with computationally demanding or particularly memory-intensive applications should be able to choose a 64-bit version of Vista from day one, provided they have a 64-bit processor to run it on. (The other potential roadblock for running 64-bit versions of Windows is the availability of device drivers, so Microsoft is leaning on independent hardware vendors (IHVs) to provide 64-bit versions of their device drivers.) Microsoft has said that its preliminary performance testing shows that existing 32-bit applications often run faster under 64-bit Windows."
My view on performance is that you can get a 10% performance boost over 32-bit, but pay a 40% premium over 32-bit. And what will the performance increase be used for in Vista?
I am saddened to discover that Vista's new interface (Aero) will require beefy 3D graphics accelerators and use the OS to implement "Glass" display effects. I very much doubt that "glass" effects will increase my productivity one iota.
I'm not a luddite and anti-progress - I work in IT - but there is a great deal that is done because it is possible, not because it is necessary.
A question I frequently ask is "why does a dog lick his b*****s? Because he can.
It is a question that should be asked frequently in IT.
So my thinking is that for the best bang per buck, 32-bit will offer superior value for the next couple of years. If you have loads of money and have to have the newest and whizziest - MS and intel shareholders just love you!