I simply cant believe why all of you guyz are even discussing this topic and kinda fighting over it
firstly and foremost ROBERT HAS NOT BEEN REPLACED AS TONY STARK ....
and secondly we get to see him as Tony in coming IRON MAN 3 and many other blockbuster movies.
and thirdly isn't it completely HIS choice whether he wanna continue being TONY STARK.....IF he wanna continue this role or leave it we as his truly faithful die hard fans will completely be on his side and cheer for him ,appreciate him and BELIEVE in him Forever .
I personally really don't even care what character he plays or leave ....what ever he does he does it BRILLIANTLY and whatever he doesn't like , he doesn't do it
I think he knows when it is enough.