If you look here there's a bit that says "It was bordering on inappropriate. You can't have s****ing in the Tardis."

Normally, you only **** out offensive words, and the only one I can think of that would fit is "shitting". If there's no shitting allowed in the TARDIS, that would explain the lack of toilet facilities, but not really why Martha's not allowed to appear in her underwear.

Or am I thinking about this too much? Yes, probably.

In other, more interesting news, China has blocked LJ. This is probably because of the rampant free speech.