The only two things missing with polls IMO is the ability to display a user name when they vote. And set a limit for poll option. So 1 poll question could have 3 categories but you only can have 1 person on cat 1, 4 people on cat 2. etc.
It would help in signup for events
The advanced quoting feature I see on these forums right now (quoting based on selected text) is such a great thing to have! Once you are used to it, you will be missing this in almost every other forum software. XF really becomes more and more attractive for me!