my absolute favorite thing was that everything was in Rome... you didn't have to deal with as many load screens as you did in the previous two. My least favorite thing is the cliffhanger T_T
my favorite thing about AC Brotherhood is basically everything. but the most thing would have to be calling in the assassins in to do your own dirty work. XD
i like the brotherhood, and i like the size of the adventure. also, love the multiplayer. things that i don't like once you start last mission you have to start all over to play as ezio. the last mission is confusing and you kill the girl (who's name slips my mind at the moment.)