TL;DR: My opinion: If you have the RAM and Hardware to comfortably run Windows 7 64-bit, you should consider it now than waiting on MS to stop XP support. The only advantages with 7 are the same advantages for any other program under 7. 7 64-bit in particular handles 32-bit application isolation quite a bit better (meaning one errant 32-bit program doesn't bring the whole computer crashing down). 7 (like vista) also moved the audio layer up and instanced it between programs. One cause for total crashes in XP was a program hooking the audio layer and going kaput, making all programs also hooked into the audio going kaput with it as well (and since the OS likes to use audio and the audio was so low level in XP, XP often went down with it all as well). That seemingly simple change, however, caused more than a few headaches for driver developers as they found themselves separated from direct hardware access, and some formerly popular hardware in XP ended up without support in Vista and 7 (though 7 does quite a bit better with legacy stuff than Vista did). XP's support is already at "end-of-life" (which doesn't mean support has ended). Support for XP is supposedly dwindling with Microsoft (and XP-64 already has almost negligible support -- Office 2010 won't install on it). With Windows 8 on the horizon, it's anyone's guess how long MS will maintain XP support. Given how MS was forced to support Windows 98 long past their planned schedule -- it ended at the scheduled time for WindowsMe (along with Me), I would not be surprised if XP ended up the same due to many organizations (including governments) still using XP (like it happened with Windows 98). Then, there is the learning curve. Vista moved many common things around and 7 moved even more. Some things are eventually easier to get to in 7, but it's like moving to a new town and not knowing where the grocery store is for the first couple of days. It uses more RAM than XP. If you're using Windows 7 32-bit, you can expect to hit the 3GB limit a bit more. 7 64-bit (with its 32-bit WoW instancing) with plenty of RAM allows a lot more 32-bit programs to run concurrently. The number of 32-bit programs that are LAA (to make full use of their individual 4GB address range on a 64-bit OS without needing to account for OS-reserved space) is increasing. Steam (EA's Origin competitor) is now able to launch 64-bit applications, though the number of 64-bit games is very minimal. For the complete Windows 7 Aero experience, you need DX10-capable hardware and DX11 is officially supported in Windows 7. (Unconfirmed rumors that Windows 7 will also support DX11.1, but for now, the only confirmation is that Windows 8 will have DX11.1.) If you're itching for an XBox, Windows Phone, Zune interface, wait for Windows 8. It has "Metro" pasted on top of Aero. It also has an improved Hibernation method that replaced shut-down by default. (And for those that dislike the Zune interface, Aero is still there with a key-press.) For those that have Windows 7, I cannot yet find anything worth mentioning in Windows 8 that would convince me to suggest upgrading when it comes out. Also, consider how the Windows 95 and Vista Aero interfaces had to go through a second iteration before they got it right (for the most part). Windows 8's Metro is the first iteration of its kind.

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