That's still my old email address (slightly mangled), BTW, I've switched provider several years ago. If you actually do an advanced search for my name, Google Groups finds about 7300 posts by me which is actually even higher than the number of posts by their listed top poster!
But as I'm not the only one changing email address now and then, the other people's count may be quite a bit higher than listed, too. So I'll not jump to conclusions.
Other names in that list I think I recognize are Larry Rosler (1), Tom Phoenix (3), Anno Siegel (4), gellyfish(5), Tom Christiansen (6), nobull (8), Benjamin Goldberg (9), Tad MacLellan (10). I have no idea on number 2.
According to the same stats, the frequency of posts in that group have indeed seriously declined since the highdays, which apparently were around 1999-2000. Anybody else remember the "Fat Alaskan Electrician", from back then? Ah, how the time flies...
Update: I knew I shouldn't jump to conclusions. A search for Abigail finds around 9100 posts! But he changes email addresses quite often, that's why he doesn't show up in these stats, that are grouped by email address, not by name, or (ideally) by person.