Polls are just what they are - samplings of a whole. People who say, "You can't get a fair poll on these/those boards. Don't take too much stock in them." Whatever.
I think that's a pretty piss-poor excuse. I think that if people were sitting around, clearing cookies and revoting, the numbers would be huge - not to mention that they'd be a whole lot more votes for 4e, IMHO. And if that was being done, on both sides, they would cancel out and the percentages would be the same. Based in these votes and things like the ratings at Amazon, really tell the feedback of 4e. This edition is shaping up to be a "love it or hate it" edition.
What's funny is that if the vote was vastly in favor of 4e, I doubt anyone would be arguing its validity.