Could you give us a link back to the main MO page from meta.mo? It's kind of annoying to have to reopen the page from scratch (or open a bookmark) going back and forth.

@Scott, Anton: if you want this, I've just done something similar for the n-lab and you can download the "extension" here:

http://www.math.ntnu.no/~stacey/documents/PseudoTabs.tar.gz

Obviously, change the occurrences of 'nlab' to 'mathoverflow'!

(It's dressed up as an extension simply because something like this shouldn't involve hacking the main code, but it is really only one significant line of code and it isn't a proper extension in that it's not "easily" customisable; there may even be an extension that already does this but it was quicker to write a hack than to search the main website!)

The more I hack PHP, the more I detest it too.