No doubt, plenty of you will be socializing tonight, either at a bar, at a party, or taking in a movie and popcorn.
And no doubt, someone else (not you) will say something incorrect or just plain wrong. Heck, they may even commit a tiny social faux-pas, such as ordering a drink from a different waiter.
Your urge will be to correct them, either by explaining they have their facts wrong ("The 'h' in 'Thames' is silent") or that they broke a social taboo ("You don't order drinks from another waiter.").
Resist this urge. It's impolite to correct someone in public. If this is your mate/partner/significant other/sister/brother/mom/dad/you see where I'm going with this -- you may correct them privately, after the festivities. But do it in a lighthearted, loving way.
When is it okay to correct someone in public? If they're drunk, and insist on driving home. The right response is, "No, you're not, and I'm calling you a cab."
Have a fun, safe, polite New Year's Eve, everyone!
Cheers, and I'll see you in 2010.