Good question, and I'm personally rather split on the subject. I caught a fair amount of the Roger Clemens trial, and one has to wonder if he deserves Hall of Fame status. On one hand, steroids do give you an unfair advantage. Steroids during sports games are like Wikipedia being used during history tests. But on the other hand, just how much of an effect do the steroids have on players' performances? Perhaps they would have reached those milestones without them(which comes up in the case of Barry Bonds). Who knows?
Anyways, I suppose their titles should be removed if it can be proven that they used them, and used them often enough to seriously impact a record. Otherwise, it would be simply tainting someone's name over something which probably had little effect in the first place.