My high school class met for our 10 year reunion - then again, I think, for our 20th? And since then, I don't think there has been a big reunion, although there were some last minute get togethers involving a very few people.
Funny you should bring this up... my class is having a class reunion this coming Saturday, I won't be there.. allow me to explain, and it won't be a 'good' excuse.
My wife's family is having a 'semi-reunion', (only a part of the family), on the same day... that's where I will be, <sigh>
I think you and Greg make an excellent point about 'old' friends being best friends. My high school class graduated about 130 of us, only 20 of those from my home town and attended my grade school... guess who, almost inevitably, gravitates towards each other when we do meet?
I should note: My High School drew from 4 surrounding towns, not to mention the vast countryside of farms... some kids traveled 35 miles, perhaps more, to attend High School.