Same here - the problem is real and indeed very annoying. Unlike in the screenshot, for me the tabs often also cover the time remaining.
(And btw a similar problem in online chess: If the opponent is on vacation, the displayed vacation message is covering parts of the info directly below the board too.)
For a couple of weeks now, the tabs on the vote chess page have covered up some of the board. I have tried Firefox v13.0, Safari, and IE. Here is a Firefox screenshot:
Several other people have commented that they have similar problems. I can provide additional information if necessary.
Thanks.