It features onboard MPEG-2, MPEG-4 and DivX hardware compression so your Mac can spend its processor cycles on more noble causes, like curing diseases. [While I haven't used the product, I hope that they quote this post in their marketing materials to make allusions that their product somehow cures diseases.]
The EvolutionTV has coax, composite and S-video in; USB out. Yes, it is odd that they chose USB over Firewire for a Mac product. It also supports NTSC and PAL, for our European friends. I can't find any size information on the site, which is important if you're planning to duct tape it to the back of your plasma TV next to your Mac Mini.
No HD support and no word on the software other than a mention the fact that it is inside the box. At $280 it's $20 cheaper than the EyeTV 200 and it ships March 15th. That's pretty soon, hopefully they'll replace their rendered picture with a picture of the actual product by then.