Go with a Google Android phone! If you have the option of getting the Samsung Galaxy S get it! I don't say that becuase I own one, I say it because it is an extremely feature rich slick phone that, in my opinion, outperforms the iPhone 4.

It's got the 1GHz snapdragon processor... comes with Google Android 2.1 with 2.2 coming out (2.2 includes features that improve the efficiency of it resulting in faster user experience and browsing)

The nicest thing about it in my opinion is the screen. Samsungs AMOLED screen is an extremely vibrant screen. It's sex for your eyes, litterally! lol It's thinner than the iPhone 4 and alot lighter than the iPhone 4 plus allows you to CUSTOMIZE the way your desktop looks rather than the mundane iPhone desktop which is just a giant list of ALL your apps (booooriiiing....) check it out, and other Android phones.

I'm not sure what the Windows 7 phones are like but I've heard great things about them seeing as they are built off the Zune interface, which is pretty slick. I used to have a Windows phone and they were GARBAGE GARBAGE GARBAGE!!! but the Windows 7 phones (now that its built off a different interface) is something I would definitely consider. I'm still pro-android but would definitely take a Windows 7 phone over an iPhone ANYDAY. Hope that helps!