I usually don't like to engage in the "this doesn't belong on HN" game, but the fact is that most of us who enjoy XKCD already read it, thanks to the magic of RSS or knowing what day of the week it is. So basically, if you like XKCD, this is old news, and if you don't, this is boring news. Summation: this doesn't belong on HN.
Hmmm, I agree with felixc, but you Mr. ars make a good point. Perhaps when submitting the comic it should come with a title in no way obviously related to web comics?
Something that would not interest the digg crowd. Then we get to discuss Godel and Russell, and people like me and felixc feel less need to complain.
There is no more relevant Hacker News than material relating to sexual fetishes. PG, you might want to rename the site "Sexual Fetish News" just to make that clear.
Thanks for the karma, folks. I'm here all week. Don't forget to tip your waitresses.