If you are into comic books you will enjoy it, they are blatantly setting up for The Avengers (Black Widow, reference to New Mexico i.e. the hulk, show Thor's Hammer at after the credits, captain america's shield used to prop something up)
For those like me who don't know too much about comics (had a friend walk me through it all), it was mildly disappointing because I was in the mood for brain numbing fighting and action.
