Having just gone through replacing our old bug tracker, Arctic, we choose to replace it with FogBugz. I looked at about every bug tracker out there, and for our needs FogBugz was the best fit. It has a Tracker, WIKI, and Forums built in and supports importing bugs/wikis from some of the more well known alternatives. It also has an XML based API which we have found very usefull and well documented. I would defiantly recommend checking them out, they have a free 45 day trial.
You are posting on slashdot, therefore we all know you do not have any ex girlfriends.
"Don't talk to me about disclaimers! I invented disclaimers!" -- The Censored Hacker