Just tried again and...nope, you can't shoot tethered with a 5D on Vista 64 (as of 12th April 2009). Canon have indeed released x64 versions of ZoomBrowser, DPP and EOS Utility, but no driver for the 5D. You can use ZoomBrowser and DPP, but EOS Utility just sits there lamely looking for the camera. As I mentioned in an earlier post, the only current option (I'm aware of) is to run another version of Windows virtually, or to have a dual-boot system. What a PITA - how long have Windows x64 OSs been around? Windows XP64 was announced in 2005! I'm wondering how 5D MKII and 1Ds MKIII users are faring - the North American Canon website doesn't appear to have any drivers available for any operating systems available on it's website (as of now, this minute) for either of these two cameras. I know writing a 64bit version of anything isn't a walk in the park, but four years for one of the worlds biggest corporations and still nothing, not even the x64 RAW codec...mmmmm...I don't think so.