I haven't decided yet. I like WP and Android both (iPhone is not on my radar). I am not under a contract now, and I am pretty content with my Focus, so I feel pretty relaxed about waiting and seeing what comes out. I'm very interested to see how Skype is implemented on WP, and also very interested to see if new handsets will come to market between now and Christmas. Not to mention CES and the Mobile World Congress. I have one good eye on the Titan too... if I get that, I will be on a contract again, and would probably give my Focus to my daughter.
As I say, I am content just watching for now. I like both the Android and WP ecosystems, and my current handset runs smooth and has all the major apps. Interesting times for cell phone fans, to be sure.