The crusader class and the removal of the AH has me most excited. Having something to play for in finding my own loot is going to make the game a lot more fun to me, instead of feeling like i have to go out and buy high end pieces on the AH to get through a tough section of an act.
For me what really got me excited was a numerous amount of things! But what really stuck out to me the most was the INTRO video and the video of the epic Crusader! Excited to start sanctuary with the crusader snd his mighty shield and holy hammer! Paladin nostalgia anyone?! Through the burning hells and to the high heavens!