I've always preferred reviving old topics vs. creating new ones. A couple months isn't that old. Five years? Well, okay, maybe.
People will react either way. Revival leads to shock and "WHY DID YOU BUMP THIS?!", whereas creating a new one leads to linking to other topics and "DON'T YOU SEARCH?!" (...Actually, every once in a rare while people are happy when a topic's revived.) So if you're looking to avoid a reaction, you'll have no luck. ;)
While there's no rule against "Necro-Posting" (except bumping for the sake of bumping), my advice is to search for the topic, and if you can find one already made (especially if had a bunch of activity in it), just revive the topic, assuming you have something relevant and worthwhile to say. If there are multiple topics about it, just post in the most recent one and/or one with the most activity. Of course, if you can't find anything, just make a new topic.
If it's a poll that's been done before, make your poll different somehow if you're not content to revive the old one. Also, polls can always be added to non-poll topics if you ask a mod or the topic creator.
