Bing's own comparison site "bing it on" shows that most users prefer Google's results[1], even though the comparison uses results modified to favor Bing[2].
dear Googler, you made me waste a bit of time: trying to do that by using tweets isn't accurate for obvious reasons. Power user vs normal user, motivation to tweet, bias against Microsoft etc. The other post was confusing as hell, I couldn't make out his point. Absolutely no data, other than suggesting that the poll was rigged. It may very well be.
Either way, if Bing narrowed the preference to 10%-20%, it's a great feat. Personally I find Bing lacking on obscure terms but most people wouldn't care.
[1] http://blog.paulnshapiro.com/bingiton-google-wins/
[2] http://www.punditpress.com/2013/02/the-bing-challenge-yes-it...