Does anyone know if the HV10 will work under Vista? Especially the 64bit version?

HV10 isn't software, so it will work :)
joking aside, what software are you talking about? The included USB/still-photo aquisition/transfer/management stuff (ZoomBrowser etc)?
Don't know on that one... I just use a USB cardreader, rather than slow camera usb port anyway...

There is no included video editing software, so take your pick of editors, that you desire, and check if they work on Vista...

that said, I'm not sure any of the NLEs DO work on Vista yet. Likely Vegas7. I don't think the others do yet.
Unless you have a new mfr PC that comes w/ Vista as no choice, I would stay clear of Vista for a while yet until everything settles... eg HW drivers, esp 64bit!!, software compatibility & upgrades/patches, GPU video enhancements enabled, performance issues fixed, etc...

I'm running Vegas 7.0 w/ Vista Ultimate... runs just fine... importing footage from an HV10 without any issues...

:)

(I use firewire for transfer... )

32bit btw, I didn't go with 64bit for lack of drivers out... 32bit Vista can use XP software and drivers without any issues that I've seen so far...

Using a FireWire card and Vista ultimate, importing and editing in Premiere Pro 2.0 works fine. No worries.