Adobe released an update for Shockwave yesterday, with better support for Vista.
In my cursory test of the new release on a machine using Vista, it seems that hardware acceleration of Shockwave 3d content is working again! SPi-V content now works like you'ld expect it; nice and smooth.
Next on the confirmed list of things to come: Updates for Mac Intel and unicode!
PS: I wonder how many people are going to 'get' the logo mashup I did ;-) No, that's not the new Shockwave logo.