Yeah yeah I know, best is probably a bad way to phrase this. But I need some pros and cons. I need a new phone and if I'm going to get a smartphone and pay all that money, I better get one that I can develop for, and games are what I want to make (not apps).

So the way I see it is the iPhone would be a bit too expensive to get into. I currently do not own a Mac and do not know Objective-C, so both of those things would be major road blocks to getting an iPhone for game dev purposes. Are there any really good or bad things to know about iPhone game development?

Windows Phone 7 is pretty attractive to me, since I already have a basis in XNA and it would be pretty easy and cheap to pick up. For game development it looks pretty attractive.

After that, my research kind of dies. I have no idea what the deal is on Android, RIM's OS or any other mobile OSes. Does anyone have any experience on these?