Phones, Phones, Phones...

I have a bit of a dilemma. I need to get a new cell phone, but I can't make myself decide on the phone I want. I have literally gone back and forth between the MyTouch 4G and the HTC HD7. They are both smart phones, but very different. One runs Android and the other runs the new Windows Phone 7. The nerd in me can write apps for both, though it might be a little easier for the HD7. I just don't know what to do. I am just going to have to go into the store and take a leap of faith...