Other key points from my experience:
-I use the paper features of Notability to take notes with my students as I teach
-I import pdf's of all documents necessary for class from my DropBox account. My pdf's (usually documents I've created in Word) then combine into my notes for the day.
-I auto-sync my Notability notes back to my DropBox account for safe-keeping. This way, if a student misses class, I can email the file directly to him/her as a pdf--very slick!
-Once in awhile, our wireless will kick me off from the network, requiring me to re-connect/re-mirror to the Apple TV. We're still hammering out some networking issues with the Apple TV's, but this has not been too problematic.
-The ipad is a little smaller than my tablet pc, which takes some getting used to, especially writing while holding the ipad, but is not a huge deal.