I dont suspect this thread will get many views but I'll keep posting my favorites for a reference later on...
Plants v Zombies
This one needs no introduction, fun game and perfect for the iPhone. I wish they would update for higher resolution iPhone 4 display though.
This game is pretty cool but wont last very long. Basically all you do is align things on the screen to make the image complete. Art direction is nice but wont last long since there are only 100 puzzles and each puzzle takes like 30 second at most.
One of my favorite type puzzle games. Basically there are numbers on squares and you have to connect that number to a square with the same number by using that many squares to get to it. Then the finished product is a pixelated image and it gives a quote. Fun game.
The premier first person shooter on the iPhone.
I dont know how to describe this game... its kind of like an action adventure. You go around on a boat battling other ships and shooting up islands. Looks nice, I havent spent a crap load of time with it yet.
Very simple quick fix game. Fruit gets thrown on the screen and you have to "slice" them with your finger before they fall. You also have to avoid bombs being thrown up with the fruit.