A lot of critics went to see Captain America: The Winter Soldier and many of them have tweeted their reactions, which is the only thing they can say at the moment. All of them have one thing in common, they all think it's very awesome and this excites me to no end, April 4th cannot come any sooner!
On a similar note, we learned that Joss Whedon filmed one of the two post-credit scenes for the movie, this is very important and peculiar. This might not be the movie before Avengers 2, but it will possibly be the one that sets up that movie, so it makes sense that Joss Whedon films one of the post credit scenes because he connects this two movies in that way.
I wasn't one of the critics so I cannot say how awesome the movie is or how relevant these post credit scenes are and how much of their importance is that Whedon did it. But, nonetheless, these are very exciting news.