Google Nexus One or HTC HD7?

[Agas]

Hello, I am planning on purchasing a new smartphone, and I am on T-Mobile USA. I have looked into the Google Nexus One and I will buy it through Craigslist, but I have seen this new HTC HD7 and now I am in doubt. I like the Android operating system, and I also crave the Windows Phone 7 operating system (I do own a Zune HD, thus I know what to expect and my sister owns an android device, thus I know what to expect). I do not like physical keyboards, or Samsung's TouchWiz 3.0 (all of which are on T-Mobile). The specs on each of the devices are the same, except for the 4.3in screen (which is a snug fit in my hand based on my experience with my friend's EVO 4G). The software on each is different though. I do have XBOX LIVE, but I do not have the "Gold" membership. I do watch a lot of Youtube content, but I barely watch that content on the go (experience with the iPod Touch). Although, I do browse the web quite often, Windows Phone 7 has smooth scrolling and pinch-to-zoom, Android has fast web page loading, Windows Phone 7 has Office (which I don't think I will be using that much on the go), and Android doesn't. Can you please tell me which phone I should get?