Looks like Mozilla is entering the smartphone market. They have their own mobile OS now. It should be interesting to see how it fares up against Android, iOS, and WM.
The ubuntu mobile OS does look pretty good. Better than the rest atm I'd say. I like that you can hook it up to a monitor and use it as a full computer as well. That could be pretty sweet for playing games. I think I'd be more inclined to get a firefox or ubuntu phone than the other two. Firefox and Tizen both have industry and telecom backing from a number of companies though so it would seem likely that those two are going to succeed at least to some extent. It would be good to see some ubuntu phones as well though.