Well I downloaded it earlier and my experience hasn't been the best:
1. The game stops every five seconds to go and tell the EA servers what you're doing. It's plain annoying. It's the same idea that made Dragon Age: Origins, a single player RPG, whine at you for not having an internet connection.
2. What numbskull decided that you shouldn't be able to abort the 'search for games' process? The only way to get away is to use the Xbox Guide to quit the game entirely. There's no indication of progress, the demo just sits there indicating it's searching for a game with no indication it's working and no way to escape.
3. I've tried to find a game about five times now. Four of those times it found a game and told it didn't work, and it was all my fault. The other time it sat for five minutes and failed to find absolutely anything.