1) You start writing lists like these
2) You claim that you're the next Avatar
3) You've tried to reach the 'Avatar State'
4) You now have a new respect for Asians, besides that you can copy off of their tests and homework
5) You start quoting your favorite character; and in the weirdest places too
6) You can actually spell Bryan's last name perfectly
7) You know who Iroh's new voice actor is (who IS he, anyway?)
8) You spend some time each day trying to find Mike and Bryan's phone number, email address, etc.
9) Your mind and gallery is filled with Avatar
10) You don't laugh every time you find a screenshot/pose in the show when on