Aha! I feel an excursion to Barnes & Noble coming on!i agree with all of jim's (even to the humor references - have you read jasper fforde? if you like adams, you might like him), and the religious one.
Smoking is a good one, though I haven't dated a smoker since I quit the last time (1 year, 10 months, 15 days and counting). I can handle bars again without going insane, and I still hang out in the smoking areas at various customer sites. I honestly don't know what it is about the broadcast business, but all of the chief engineers at all of my TV stations smoke. Don't know if that one would neccessarily be a deal breaker, as long as she agrees to be banished to the patio with Tomcat to light up.
Excessive piercings are unattractive to me, though some of them can be quite interesting...ahem. Whew! OK, I'm back now...where were we? Not sure they'd be dealbreakers for me, but she'd probably get tired of me fidgeting with the more prominent ones.
Any sort of psychotic behaviour would (and has in a couple of cases) definitely get her voted off the island. Particularly any that prominently feature sharp pointy objects or firearms.
Addictions, particularly to illegal substances, fall into the realm of "needs professional help", and would at least require exile until it's fixed, possibly outright banishment from the kingdom if it's bad enough. Yep. Not gonna play any of those games, either.
Cheers!
Jim