The overlay scrollbars certainly looks good and functions quite well, but I find that it can sometimes be problematic if you're trying to scroll using the scroll thumb. The orange bar is the target when you want to drag the thumbs but the bar scales with the content in the particular window. Basically, if there's lots and lots of content then you'll have an ever smaller target to aim for. When using just the mouse scroll wheel there's no issues but since some users are used to dragging on the scrollbar (or, may not even have a scroll wheel on their mouse) it may turn out to be an occasionally slightly frustrating experience.
|The new overlay scrollbars with a rather small orange bar|
Aside from a few niggles (and the occasional crash) Natty seems to be doing just fine. Since Natty Beta 2 replaces the traditional Release Candidate this cycle it should really be pretty stable at this point. From here on out there should be nothing new landing. It's bug fixes all the way.