I’ve seen the twitter, but I see a lot of different between the both themes.
The first thing, the circle style is from http://tympanus.net from a tutorial, so is not a rip if we are talking about the circles.
Sorry about the other comment, I haven’t seen this link : http://themeforest.net/forums/thread/wordpress-gpl-and-themeforest/101337 sorry for that, cheers 