I, for one, am incredibly excited. Azumanga is a hilarious series made up of vignettes revolving around some pretty unique and quirky female characters. Azuma's manga upon which it's based is a 4koma comic strip, and in my opinion helped pave the way for later such strips to be made into anime (Lucky Star and Sunshine Sketch, anyone?). Okay, admittedly, it's not like it was the first-- Sazae-san, whose anime adaptation started in '69, was a 4koma, as did Di Gi Charat, but still.
I poked around the 'net to see if there were any free (legal) Azumanga episodes available, but I couldn't find any (I wonder if ADV still has the anime license?), so you'll have to make do with the OP sequence, which is still awesome.
I wish we were getting something for the 10 anniversary too...
CHIYO YOU'VE DOUBLED YOUR AGE T_T
Might be rewatch time soon.
Yay!! Happy Azuversary :)