Also implied here is the ability for a poll to be both live and closed.

An example would be a "Who do you think will win the ____ match?". It would need to close before the match finishes, and no human may be there to do that manually.

I was thinking cron could do this, or some sort of pseudo-cron. With the bookmakr addon I am working on I assumed I would have to use cron to handle the closing of bets, which will be another learning curve if so :P

Conversr forum polls now have this feature. The regular site polls addon should be considered for very basic straw polls only, while Conversr polls are particularly sophisticated (and quizzes sophisticated in a different ways).