already was one a few weeks ago, but it's participation was lower.
A lot of older threads get dug up to the top when new members come along and don't differentiate new from old by looking at the 'last post date'.
I suggest that formal polls should be given a 'time to live' window, and are closed after a certain number of days (or weeks). Then 'fresh' polls could be taken at different times to guage changes in trends. JMO.