There seems to be a growing consensus that you can’t say “two thousand-something” any more — you have to say “twenty-ten” or whatever. This has been the only century since the acceptance of the Gregorian or Roman calendars in which English-speaking people have referred to a year by saying the word “thousand.” This has mainly been due, I suspect, to the grammatical influence of Stanley Kubrick‘s 2001: A Space Odyssey. I’ve been a twenty-something advocate since ’01, to no avail.