I personally loved the way that Thor delivered the "he's adopted" line.
No specific lines here, but one thing that I loved about the movie was several things that happened very suddenly and unexpectedly:
1. When Loki started going into a tirade, yelling at Hulk that he was a God, basically saying that he was above fighting a mindless monster, blah blah blah and without warning, Hulk grabs him by the leg and whips the **** out of him.
2. When Coulson told Loki that he would fail because he lacks conviction. Loki again started in on his speach, and without warning Coulson blasts him in the face with his Destroyer-inspired gun.
3. Hulk punching Thor.
Awesome.