I have been working on 64-bit adoption for many years now (some say too many), first with Itanium and then more recently over the last 4 years with X64. Clearly there has been a shift from 32-bit to 64-bit on the server for obvious reasons, with some products from Microsoft like Exchange ( and soon Windows Server ) been 64-bit only.
But what about the client - tbh it has been dragging well behind, with consumers ( through OEMs) not really seeing demand. However I have been looking at the figures for 64-bit client adoption over the last 3 months and there is clearly a significant change happening in the market. After years of slowly changing the mix from 32-bit to 64-bit systems, PC manufacturers are significantly increasing production of 64-bit PCs running Vista, typically with 4GB or more of memory. With recent drops in memory prices, PC manufacturers are producing a 64-bit PC that’s priced competitively against a 32-bit PC and that seems to have driven consumers buying new machines to go 64-bit.
I think that this is great news for the industry. This gives the OS more space to breath ( in 32-bit it is always competing with Apps for Memory and processor ) and will give consumers and application developer writers more opportunities to build and use a new generation applications running on the client which can use this new capability.
Finally the feedback that I am getting from the external community about 64-bit Vista is really encouraging; they love it and would not go back.
Lets hope the trend continues. And no I will not be evangelizing 128bit!!!