I have a JVC GR-D320 miniDV camcorder that has a FireWire interface. I recently upgraded to Windows 7 RTM (64 bit, fresh installation).
When I connect my camcorder through FireWire, I can see it in Device Manager without any warnings or problems, but I cannot capture videos from my miniDV tapes. After connecting, AutoPlay displays "Import Video could not find a compatible digital video device. Verify that the digital video device is properly connected and turned on."
When using Windows Live Photo Gallery after selecting the import option, my camera is not listed.
The camera used to work perfectly on the same hardware before upgrading to Windows 7 RTM 64 bit (it used to work fine on Windows XP SP3 32 bit).
Googleing revealed that people had the exact same problems in Vista, but no solution was provided.