Many times each day. Of course I check out the video section the most for comments, etc, but my favorite section is the discussion section. I check the humor section every day for new jokes.
For me it used to be very rarely.....every couple of months. Nowadays it's a little more frequently - quick checks maybe once or twice a week to see if anything interesting is being posted...
Pretty much every day to check for new clips, new discussions or who might be ditzing me - sometimes I get pissed off with some of the idiots on here ditzing me, though, and don't look at it for a week or so.