On Ubuntu 11.04 I am having two issues, but not on OSX.
When I am in two column view, I have a hard time dragging tabs over to the right hand column. What happens is I have to go above the row of tabs, and then drop it down into the right hand list. If at any time I go under this line of tabs, it will open the tab in a new window. If I go under the line it will lock in the action of opening an new window without actually doing it until I release the mouse, so it looks like the editor has become unresponsive.
When in full screen mode, It's tough to select tabs, or click on the close tab buttons. I have to click on the lower have of the tab. It seems like unity or the upper task bar is grabbing the mouse when it gets that high.
Other then that, great editor. I've been looking for anything to get me off Aptana. TextMate didn't fit the bill because it had to be cross platform. Ever since opening up Sublime 2, I haven't looked back.