Badaboom - does what it says on the tin
 

I'm not so sure how useful it's going to be for me day-to-day, but I just picked up an Nvidia 9800 GTX+ and Badaboom. It works, rendering to H.264 at around 20fps for full 1080p HD video, and somewhere around 110fps for SD videos.

It's of limited utility, but as far as that utility goes, I haven't found anything better. Basically, I import all my raw footage from a particular shoot into a Vegas timeline, export as a 25mbps m2t file (something like 30, 40 gigs per,) and then use Badaboom to create an archived file that'll fit on DL DVDs. These DVDs, I can then ship off to my movie partner in New Zealand, as well as keep around for "worst case scenario" backups in case of hard drive crashes.

Of course, since I'm still relying on the CPUs to render out an M2T file, the longer the file is, the more use I'll get out of it.

Additionally, I can begin editing the next piece of information in the CPU-based Vegas while rendering in the background with the GPU-based Badaboom.

So, I think it's worth it.