New Weekly Shonen Jump issue has announced the 5th Official Characters' Popularity Poll.
I don't know more details becouse I can't translate the scans (maybe Aohige or CCC can translate them and explains us how poll works) but I think we will have the results in October-November.
You can see the results of the other Popularity Polls here.
http://onepiece.wikia.com/wiki/Popularity_Polls
We can vote for our favorite characters while we wait to the official results. How about if we choose our 15 favorite characters?