I think threads to celebrate a member is fine, like if I made a thread "so and so is fantastic"..then that should be okay.but adding a poll is kinda wrong..someone sometime is going to vote a negative and needlessly hurt someone's feelings.
people really shouldn't make them for them selves though..those are kinda on the same field as the "do you like me?/do you hate me? "threads...and those are yucky.