Appeals to a wide range of audiences. The Killer App?!?
While $80 is a lot to spend after you've already plunked down $50 for the game itself, you get double the songs (almost all from the previous Xbox version). My only complaint is that the awards and unlocks only count on the original songs (not ones downloaded). Sing and Dance is TOUGH, but a great new feature.
Overall, this is probably the most played game in our collection. I wish I could get a referral bonus for everyone that has purchased after playing at our house. Turns our Home Theater into a complete Entertainment Venue itself.
Could be the Killer App for the Xbox, if more people knew how DIFFERENT it is from real karaoke (which most people hate).