I changed from Duster to TwentyEleven and saw two things which actually might be bugs (or features ;-)):
1. The featured post features the share this buttons on the Showcase page although they are deactivated for "overview". This wasn't the case with Duster.
2. Linked images in text widgets now have a slight border around them although the html code doesn't provide for one. I guess it's not intended.
Blog url: http://gruebler.wordpress.com/