Some lessons from a 1-day PC meeting (nothing really new, but I thought I'd write it down):
1) Face-to-face PC meetings involve far too much sitting. Especially if you fly in and out on the same day. (I know there's a time tradeoff in scheduling an "exercise break", but seriously...)
2) Conferences with 20% acceptance rates are, by their nature, a bit depressing -- it's hard to reject so many papers, some of which simply MUST be pretty good.
3) It's easier to argue how a paper is flawed than to argue about how it's making an important contribution.
4) Taking reviewer expertise into account is important, and one outlier can cause problems; sometimes papers live on longer than they should if one reviewer gives too high a score, and sometimes papers are put way lower in the ordered list than they should be because one reviewer gives too low a score. (Of course, one expert reviewer can also bring an otherwise ignored paper back to life.)
5) There are more interesting papers than paper slots.
6) There's generally plenty of down time, when papers you didn't read are being discussed; bring something to work on quietly (but pay attention to what's going on).
7) You really do learn a lot reading 20-30 papers for a conference PC.
8) As you go down the paper list by score rank, eventually (and sooner than you think) you hit a paper that you start to question -- are these scores too high? And as you go up the list from the bottom, you'll hit a paper where you question -- are these scores too low? The rules of randomness tell us that some papers will get comparatively mis-scored in the first round of reviews, so it is good to stop and talk about the papers (and not just take the first X).
9) Hot trends come and go.
10) A steady supply of drinks (mostly caffeinated) and a good lunch can help the PC move happily along.
Thanks to the PC chairs and other members -- I had a good time. But now I'm very tired...