I think all phones with MotoBlur actually *are* android phones. I know the Devour is, for instance. So any of them will run Android apps; the difference is if you have MotoBlur, the phone's main screen shows the social blur stuff all the time, instead of having to run apps to get to that stuff (like Facebook apps, etc.).
If you are always in Facebook and such, you probably should get a MotoBlur phone. But otherwise, any Android phone will work - and remember, with the right apps, any Android phone will still do all that social stuff (there are free apps for Facebook, Twitter, etc.).