Good article on burnout for web professionals, published by Scott Boms on A List Apart.
I've been there, several times in my previous jobs. I restored my balance by going as far as changing jobs, because I could (radical, but effective). And I'm this close to another one right now, because of an unfortunate mix of complicated project, bad design, and craptacular code I'm forced to work with. And in particular because of one abysmally crappy browser that didn't give a damn about web standards until only very, very recently. I could use a few Microsoft developers for shark feeding here in the lagoon, although I would feel a bit guilty to feed them with such junk.
Believe me, in certain professions like web design and IT, Microsoft's products do cause burnouts!