So, for me the monitor itself works ok in Windows 7, but WinACD doesn't install. No onscreen display for the brightness. Also there seems to be some exclamation mark thing with the USB hub though I haven't found an actual problem with the hub.
I'm using the monitor in Windows 7 64 RC without a problem, though it sees it as both a Generic PNP monitor and an Apple 23" HD Cinema Display (I'm using an ADC to DVI adapter on it as well as it's an ADC monitor). But it's nice to be able to adjust the brightness in Vista (32 bit). Not necessary in Windows 7, AFAIK.