Damien Sandow (Who?)
IMO, the most entertaining new heel in WWE in ages. He was promoted from FCW to Smackdown a few months ago which would be why you haven't heard of him.
He's basically doing a modern-day version of Lanny Poffo's "Genius" schtick but does so really well. Hasn't been in any matches against non-jobbers yet, but at initial glance appears to be decent in the ring (I didn't follow his early career so I have no clue how he performs in the ring).