Comments

johnmeyer wrote on 7/30/2006, 8:09 PM
Snapshot to clipboard

and

Shapshot to file

over at VASST will do this. They are for Vegas 4, so you may have to change the name SonicFoundry to Sony in order for them to work with Vegas 5 and Vegas 6.
jetdv wrote on 7/31/2006, 8:45 AM
MANY such scripts exist. In fact, one is included with Vegas. Just go to Tools - Scripting - Render Image Sequence.

Beyond the ones mentioned by John, there's also a version here