Heh, yea it is disgusting
I took pictures of his room a couple of months ago, as he left the door open because my dad wanted to paint it.
http://dresch.co.uk/resized/
In the first picture you can see all that white gravel stuff on the floor, that's cat litter, it's been there for about 6 months now.
I wish I'd have taken a picture of the carpet along side his bed, you can see the carpet colour/pattern in the first picture, but along side his bed, it's black, that's how dirty/disgusting it is.