Since I upgraded Vegas to 8.0, they've changed the way that effects and transitions are handled, and it took me some time to figure out how to do what I wanted. That being said, when I finally did get the right tool, it made for awesome, and did exactly what I needed it to do.
Nice bit is that I can work completely in 1080p24 uncompressed, even though I can't yet play back at full speed. Uncompressed needs to stream at something like 100 megabytes/second per stream, so if I have two streams that I'm combining (like AB roll), it's trying to pump 200 MB/sec from the hard drive as well as trying to do realtime effects. Not gonna happen with the current mo-chine architecture, but it's not extremely far away either. And really, for right now, I can live with non-real-time effects. I can do low-res previews if necessary to get the right "feel", and high-res for nanotweaking.
Tomorrow I'm gonna try playing in the new Combustion. I'm expecting that will not be without its quirks.