If you’re capturing HDV footage using something like HDVSplit, or Cineform’s NEOScene, and your HDV camera no longer appears to those programs as a capture device, or even showing up at all; then try changing the Firewire (IEEE 1394) driver to a “legacy” driver. This tends to work in the 32 and 64 bit versions of Windows Vista and the release candidate of Windows 7.
You know, just F.Y.I.