Via The Tin Man comes this helpful site listing a lot of the most common “non-errors” in English. A non-error is defined as one of those prescriptive rules of grammar or usage that fussy people insist on pointing out, even though they’re generally wrong. For example, “since” versus “because.” I agree with pretty much every point made. In this case, if a “mistake” has been consistently made since the 14th Century, you really can’t call it a mistake.
It’s certainly worth a look.
While you’re at it, you might also check out my earlier rant about “data.”