I have to say that I'm kind of amazed by the lack of vision on the part of so many posters here so far. Most of the complaints that I've read so far are either petty or short-sighted. I think this thing will take off pretty well.
What is there not to like about it?
Price: one third the price of other consoles. About the price of a top Roku model or Apple TV. If this thing takes off I can actually see it eclipsing Google TV in the media apps arena too. If the games are in the $1-$10 like some people predict, that will also be a bonus.
Openness: more open than any other consoles.
Ease of developing and releasing for it: great - Android, no expensive licenses or development platforms, etc.
Ease of use and buying games: great - looks like it will be well-designed. All games have some free element to them so you can try them first. All games are downloaded. Not having to go to a store or wait for shipping, combined with the anticipated price of the games should make for lots of game sales.
Power: fine. It will do 1080p. Sure, you won't be playing the latest Crysis or whatever on it, but look at where the money is going in gaming nowadays - casual games and mobile games. Imagine some of the better casual and mobile games running in 1080p and this thing will kill, especially if the price of the games is in the $1-$10 range.
Internet buzz: pretty strong. I keep reading about this thing constantly. If you're into games, you've heard about this.
The only ways I can think of this thing failing is if there's some major flaw with the hardware or software, or if patent trolls gang up on it and kill it, or if the game prices get inflated to significantly over $20.
Really, I have not yet read one single legitimate concern out of the other (early) posts so far. Sure, you can complain about the low hardware power, but for the price and the category of games they're going for, that shouldn't be an issue. It would only be an issue if they tried to run AAA FPS games, etc.
Ouya so far seems to be doing fairly well with the opportunity to coalesce the whole indie, casual, and mobile gaming markets on to one affordable device, and could build a significant library of games pretty quickly.
So again, what is there not to like about it?