Continuity mistake: When the guys are at the bar before going to the awards show, we see Marshall raise his beer to his mouth twice from different angles, without ever lowering it. Also, the amount of beer in his glass changes instantly between the shots. (00:03:30)
Continuity mistake: When Ted is talking about getting a blessing from a pimp, Barney's drink just disappears from the table. (00:03:35)
Continuity mistake: When Ted and Marshall are watching Sandy Rivers read the paper on TV, the items besides the TV on the TV table switch according to the angle.
Chosen answer: She was finally shown at the very end of the last episode of season 8, continuing into season 9. The actor's name is Cristin Milioti: http://www.imdb.com/name/nm2129662/.
Knever