I've been using nothing but iMovie 11 and EyeTV 3 for my gaming channel. It's all you need. I'm looking forward to Final Cut Pro X though.
You sir are a steely eyed missile man! That's what I needed to know. And if it works for iMovie 11, it'll work for BTV or anything else that can see the video stream (I believe).
Thanks! And I'll make sure to check out your channel!