lucy24 - 8:25 am on Mar 20, 2012 (gmt 0)
From what I've seen, query vocabulary continues to be the key factor in what's returned for a search. If you search with five-syllable or six-syllable words, you'll get content written in academic style. If you use two-syllable words, you'll generally get another set of results.
Once upon a time, this was easily explained: Your search will return results that are dominated by the words you searched for. Have we got to the point where this is simply not a factor?