114D - I know I've bumped old threads when they are a player profile or a recurring issue. For example, in the Farm section, the prospect profiles can be old. Those are meant to follow a guy through his minor league career and how he is doing, so I think those are appropriate to bump. Other threads, like threads on ownership, development around the stadium, and the GM seem to be appropriate to bump, although those seldom linger more than a month. finally, threads like "is there a good place to drink and watch a game" probably get cold in the winter but have a lot of carry-over year to year.
I've got a hunch people will want to talk about Desi and Espi as long as they are both here, so bumping a Desi / Espi thread is not too offensive (by the way, who is your favorite Beatle?).