Microsoft’s Vista OS has brought with it a number of issues. All of these discovered so far are related to camera drivers (or lack of drivers) that play well with Vista.
Nebulosity launches and works just fine in Vista. Not all cameras work for capture at the moment, however. So far, the ones that don’t can be traced to driver issues.
PHD will not launch as-is under Vista, but if you right-click on it, and pull down Properties, Compatibility, and set it to run in XP SP2 mode it will run just fine. This is the result of a driver compiled into PHD.
As of version 1.6.1. Full Vista compatibility (no longer need XP SP2 mode)