Well, there they are, the only three confirmed Windows Phone 7 Series prototype devices that currently exist. From left, we have the new Samsung slate that debuted today, the just-for-demos unbranded Asus unit that was the star of MWC, and the LG slider that we got cozy with at the Engadget Show. We're still hoping for more time with the Samsung -- and we're pushing for more detailed specs on all of these -- but check out some high-res crops in th