[UPDATE #1: Has iTunes 8 made your CD/DVD drive disappear? Check out this post.]
[UPDATE #2: Possible fix for the iTunes 8 BSOD under Vista here.]
I'm getting sporadic reports that Apple's latest iTunes 8 media applications is causing Vista systems to experience BSODs (Blue Screens of Death).
I've tried replicating a BSOD on both Vista 32-bit and Vista 64-bit using iTunes 8 but so far the program seems rock solid (albeit slower than iTunes 7.7). According to Apple's support forum the crash is linked to the usbaapl.sys/usbaapl64.sys driver. The fact that this crash doesn't happen on all systems seem to indicate that there's another factor involved.
If iTunes 8 is making your system BSOD then I'd be interested in learning a little more about the configuration of your system to see if I can replicate the crash.
[UPDATE: Ed Bott has an idea as to what's going on here.]