Well Hollywood has been doing it for years, making the lead actor look much bigger and taller than he realy is. They do it with Tom Cruse and they did it all the time with Silvester Stalone, and I bet there are more too.
Also Damon was great in Borne Identity and Supremacy, he could bulk up and do action easily. Plus he is a great actor, so he wouldn't have the problem some have in convincing the audiance that it was Steve Rogers on screen and not Matt Damon (
cough) Halle Berry (cough) Nick Cage (cough) Ben Afleck (cough)
I would rather see him as Daredevil but I think he might make an alright Captain America. But maybe there are some other actors out there who might be better.
I also have no problem with them having Captain America dress the the way he does in the comic, as long as they make his uniform the way John Cassidy drew it or the way the Perkins draws it now. Meaning that the blue chainmail on his chest are very defined (not like the original Cap movie), that his mask is sort of Batman molded to have more like a helmet look.
GOOD
Bad
And for the movie, much like the horrible original, I say start it out with a short scene of WWII. (and in his Original Costume and with his Original Shield.)
Then have him get unthwad in the modern times, and then move into the story. The movie can sort of be about patriotism today or something, or maybe just about Captain America coping with the life he left behind and how he feels out of touch and out of time. Maybe even splice in some flash backs.
(I also think that the people who unthaw Steve Rogers should be employees of Stark Industries. It should be Stark Industries that thawed him out and it taking care of him. It could even be mentioned that Stark wants him to be mentally and physically ready to join the team.
I would also like Jarvis, the Avenger's buttler, to be someone for Cap to talk to like he did in that Scott Kollins illustraited Avengers book. That was awesome.)
Then in Captain America 2 hav it be the story of "Bucky" Barnes. Have the villian Baron Zemo emerge (actually his son) and reveal more about Cap's past. About how Bucky was his side kick, a young soldier who helped Cap on missions and was killed (or presumed dead) in an explosion that also was thought to have killed Baron Zemo.
And in Captain America 3 it could even have some more, or less, Flash backs. Or Captain America 3 could have Cap join the Avengers.