This is a great article about using such phrasing as “x times faster” or “x times as fast.” It also brings in the notion of something “increasing twofold.” I was looking at how to calculate how much “quicker” something is for my computer science lab, so I did a Google search for calculating “times faster.” I also threw in “Apple” in a subsequent search because I remembered their recent marketing campaign with terms like “2x faster” which puzzed me because the numbers Steve was showing actually showed that the new computer is “2x as fast,” which is very different from 2x faster. Oh well. You can assume that anyone someone uses these phrases, they are wrong. Unfortunate, but true.
October 24, 2007: I believe Apple still bungles this kind of stuff. So much for mathematical precision!