I'll be interested to see how this plays out.
Many iPhone/iOS games are "casual," if not in gameplay, then at least in mechanics. Fruit Ninja is a fun game, but it's fun because it's in your hand. It wouldn't be fun on a 50-inch TV.
iOS games are so diverse that I'm certain lots of games would be great on the big screen. But just because someone plays games on their phone doesn't mean they want to play them on their TV; there's a behavioral divide there.
Someone might be interested in playing games for a moment, but loading a game on TV signals a larger interest and commitment than the couple minutes of engagement you might have with Sage Solitaire or Candy Crush.