Boxee vs AppleTV2? If you have lots of iOS devices like an iPad and an iPhone, definitely go for the AppleTV2. The Airplay is amazing, and if you subscribe to adult web sites, you'll be able to stream them to your TV using either your iPad or iPhone (as long as the airplay icon shows up)...
Now, if Airplay is not something you're interested in, I would go with the Boxee or Roku, they seem to stream a lot more content then AppleTV2 does without having to hack everything.