I've covered this show a few times at work now and find that I'm completely hooked. I think it's at least as much having the right host as subject matter. I don't know where Discovery Channel finds these guys, but they've really got a knack for engaging, charismatic nerds (see also "Mythbusters")
Granted, I really didn't need to see Mike Rowe hold a cup while a pig farmer procured genetic matter from a boar, but I've yet to see a guy with as good a sense of humor about standing knee deep in raw sewage.
If I remember that the show is on, or flip by it, sometimes I'll watch it. The one where he was with the Exterminators was great, as was the Ostrich farm. I don't know how this guy manages to stay as enthusiastic as he does for these jobs :)
I found it funny when Kirsten Dunst said something along the lines that the 4th movie would suck unless she, Tobey, and Sam were back. I think I could tolerate a Spidey movie without her. Especially after seeing how hot Bryce Howard looks as Gwen.