This is perhaps the best sumnation of my feelings on the subject;
I don't know exactly where steroid use should sit on the hierarchy of sins against the game: I think it's worse than throwing spitballs and not as bad as throwing games, but how much worse and how much less noxious I'm not entirely sure. But I do know that to date, the only otherwise-deserving players who've been denied entry to the Hall - Rose and Shoeless Joe Jackson - have been those who were guilty of infractions that got them banned them from the game for life.
Now perhaps steroid users should be banned for life, but the fact remains that A-Rod and others stand accused of violating a rule that carried no penalty save treatment at the time that they (and dozens if not hundreds of other players whose names haven't been leaked) broke it, and that today only gets you banned outright if you're a three-time offender. And I think it's a good rule of thumb that if you're allowed to continue playing major league baseball after committing a given infraction, you shouldn't be disqualified - informally or formally - from its Hall of Fame.