This came out of I Push Wood's mispronunciation thread. I've already mentioned a British tendency to use then for than, which annoys me, but there other, to my mind more insidious, misuses. Infer for imply is becoming very common, even to the extent that I've spoken to people that claimed to have never noticed a difference in meaning. Incredulous for incredible. And discrete for discreet (or vice versa) - this last once happened in a technical specification, I pointed it out just before design started and saved the company quite a bit of money on it. Any others?