I've got an iPod touch, which is iPhone without the phone part, very impressed with it. Next none work phone will be an iPhone; it's a great piece of kit, if a bit expensive. If you're choosing a contract phone and can afford it then I think it's a very good choice.
Depends on what you want Mp3 player & wireless net device wi basic fone talk & txt or 3G capability fone wi some mp3/camera/email/web function