I'm not sure why so many people think I don't read xkcd, but a metric buttload of people sent me a link to today's comic [marginally NSFW]. I thank all of you who did, but take note: given that I am a vastly huge geek, and xkcd is the most popular geek comic in the observable Universe†, rest assured I read it. I have something to add, but go read the comic first. Go. Back now? OK, so now that you've seen it, I have to note we used to make a similar joke when I was in grad school. When my roommate Erik and I ran a night sky lab, he would show students the constellations (they had to learn a handful of them and a few stars for a quiz). In the winter, when it came time to point out Orion, he'd show them Betelgeuse, Rigel, the belt... and then when he pointed out the "dagger", he'd quip, "... and if you want to call that a dagger, be my guest. But I think we all know better."
^† Or is it SMBC? We need a quattuorlitteras acronymically-known web comic stats-off.