Thunderbolt to HDMI

Well, my end goal is to send audio/video from my latest gen iMac to my HDMI TV.

A few details...

I play Team Fortress 2 via Steam on my Boot Camp (Windows 7) partition and would like to be able to utilize the "Big Picture" mode which requires an HDMI out to your TV. You can then hook up a controller via bluetooth to your "PC" and essentially be playing it as if it were like a PS3, etc.

The first trick is that since the iMac doesn't have HDMI out, what do you think would be the best way to bridge that gap? I'd assume by leveraging Thunderbolt? If I do use Thunderbolt, I'm not so sure it will work well being that Thunderbolt connections in Boot Camp don't seem to work unless they're plugged in at Startup, and even then, Target Display Mode doesn't work in Boot Camp, so why would this work any better?

Does any of that make sense? Does anyone have any suggestions to make this as close to "native" as possible?