Once more, with feeling because it's gotten even worse in Beta 3: the content of the admin screens is overflowing my browser window. And, because there is no scroll bar anywhere, I can't read it.
This is happening with Comments and with Categories that I have found so far. Please fix this soon. Seriously, this layout needs to make provisions for overflow.
Incidentally, both Categories and Tags pages look absolutely dreadful. Not to belabor the point, but not everyone has a huge screen resolution, and having two vertical columns makes it horribly cramped to read, even when it isn't being forced off the side of the window. And these pages, of course, don't have drag-and-drop modules to ameliorate the problem. Putting the admin navigation to the side of the page has already cut into the horizontal real-estate; trying to arrange those tables in double columns also is not a good idea. If you want the add-new stuff more visible, just put it on top.
Also, the Settings pages no longer have any distinguishing background. That is, it's all just text and checkboxes on a white page. If this was deliberate I think it's a very bad idea and makes the pages much harder to read.
I quite like 2.7's functionality, you know, but only when it's actually functioning.