Not really, at least as far as sharpness and contrast are concerned. I'm not a pixel peeper so doing the tripod shots was painfully boring for me, but I'm glad I did them. As M. Lointain says the distortion on the 2.0 is smaller which I like.
Originally Posted by brian steinberger
One last shot, showing the 2.8 attached to the camera and the 2.0 next to it. Not a small lens (it's bigger than my 50mm 1.5 Sonnar) but I quickly got used to the size. The filter and caps make the 2.0 look bigger in this image than it is.