Claire Danes was actually pregnant with her first child during the latter part of the making of Season 2.
All of the sailors/security guards at the Naval Observatory (Vice President's residence) saluted Brody as he entered. Congressmen are not in the military chain of command and do not rate a salute. Brody was a Marine E-5 to E-7, an enlisted man, and also did not rate a salute.
With 2.20 million viewers, this was the highest rated episode of the show up to that point.