Angry birds ain't too bad, but it is in very real need of an aiming system, see "Learn To Fly". In L2F you unlock (buy) better gear as the game goes on, but it still takes skill to win. Angry Birds requires skill, luck, luck, spam, spam, spam, eggs and luck. Seriously.
Haven't played the other 2, so I will criticize another game: Eliss. The first 3 levels are for learning (and putting in the demo). The next 12 levels get progressively harder. Level 16 is insane. Level 17 requires 3 players, I assume, who have the finger size of a 10 year old. A 10 year old from a very hungry country, not America. Maybe an American newborn. There are supposedly levels in the game after 17, but I assume they are there to taunt me.
Battle for Wesnoth is on iPhone now. Hooray. But it is dog slow on the iPhone 3G.. it may be better on the 4. Its a fun strategy game, but seriously, dog slow.