I think the avatars could be really nice if microsoft goes in the right direction with them.

For example with the new gears of wars comming out... if you beat the game on insane you can unlock a marcus fenix avatar exclusive only to those have beat the game... Or perhaps you don't have to go that far ya know... even tho that would be cool. Maybe if a player were to get an achievement in gears 2 they would unlock a gears uniform or a lancer for your avatar or something exclusive to that game and only to someone who has unlocked that acheivement.. And then not only that but you could customize your unlockable so that whoever else unlocks the achievement won't have the exact same thing as you. If something like that was done then I think it would be a nice and subtle way of showing people what games you are interested in... And maybe, sticking with the whole gears theme, there could be little animations with the props like your avatar could rev the chainsaw and give a chuckle or shoot confetti in the air and and catch some in his/her open-hand and and smile... I think the avatars are cool I just hope they utilize the potential of the concept.