I've seen many people wondering how the polls will work, and I think OpenTopic has it implemented very nicely, and to be honest, their board is what inspired many to crave polls in either UBB or vB. Don't take my praise for the OT Poll Feature as praise for OT. It's very nice software, but way to expensive for individual webmasters IMHO. But lets not turn this into a vB vs. OT debate. Here's their implementation of polls, and one I would like to see copied.
http://beta.infopop.net/OpenTopic/pa...946&m=77809659
BTW, I fully support the idea of having the option to restrict voting to registered users. It would be the best way to prevent users from cheating the system, and also give an incentive for lurkers to register to vote.