This is an interesting poll, but I hope no one seriously attempts to use it as "proof" of any trends in the Dungeon/Poly readership. Assuming EN World is an accurate model of the RPG audience is dangerous from a business point of view, because in general this site attracts the most serious, dedicated customers possible--the kind of people who read and post online nearly every day (I include myself in this cheery demographic). Our readership includes LOTS of far more casual readers, who may not feel as stridently about the issue as, say, the honorable Iron Chef. The same survey on rpg.net, for example, would be an interesting experiment, as I believe the ratio of readers over there who buy the magazine primarily for Poly is probably higher than it is here. EN World, despite being a haven for d20 in general, attracts mostly D&D fantasy fans, as I think everyone would agree.
We added Poly to Dungeon to make both magazines viable at a time when magazines are dying all over the newsstand. This is not a good period for any magazine publisher right now, and we're doing the best we can to keep putting out our magazines as long as possible. The combination of Poly and Dungeon, though not without its problems, has had the benefit of keeping the magazines in print and in distribution, which is really the whole point of the exercise.
I certainly wouldn't argue that more people want to read Poly than want to read Dungeon. That would be foolish, especially in light of Dungeon's long history as an essentially unmodified D&D-only magazine. The upcoming format changes I've outlined in other posts (fewer mini-games, more adventures, etc.) attempt to address this without cutting out Poly alltogether, which would put Dungeon at an unnecessary risk.
So, while I think it's great for everyone to post their opinions about the magazine (whether I agree with them or not), a poll like this is unlikely to have much of an impact on our decision to bind the two magazines together, and certainly can't be considered scientific or definitive in any light other than the anecdotal.
We've heard the complaints of long-time Dungeon fans, and are making changes to attempt to redress some of the most serious issues. Getting rid of Polyhedron is _not_ on the table on any level, and is not a serious option for us at this time.
--Erik