Windows had AMD64 support around 2004 (I ran the beta) but I'd say that serious 64-bit support came with Windows 7 in terms of drivers and the working out of all sorts of little details on how applications are recognized, DLLs, development issues, etc.
So maybe five or six years from concept to generally supported product. Now AMD64 had the benefit of being able to run 32-bit applications natively which made it very convenient for developers as they could do their usual 32-bit stuff on the same machine as their development system. Furthermore, users could always just run a 32-bit Virtual Machine for applications that, for whatever reason, just wouldn't run in 64-bit mode. Cisco VPN was one of these important applications. Apple got around this with universal binaries but remember, they were going from a weak CPU to a strong CPU.
ARM won't have these advantages in porting.
Will Microsoft do a 32-bit platform or a 64-bit platform first? Are there 64-bit platforms ARM out there right now to work on? Do you want your next desktop to run 32-bit Windows? When you can buy 8 GB of RAM for well under $200?
Computer companies could build and ship ARM PCs right now running Linux. They could slot them in the netbook market. Is anyone doing this? Why not?
Market Data 
Markets 
AI
