A sign that Isabelle Fuhrman is a great actress! :)
A sign someone is great in acting is how fast they go from looking happy to being completely serious. Isabelle does this succinctly. She goes from smiling a happy looking smile to a serious, determined frown in a matter of seconds. Craig Bierko does this in Scary Movie 4 too. He is laughing jovially and then abruptly stops and looks serious.
In the Citibank commercial, Identity Theft Victim Darryl appears to speak like an excited teen, talking about the things "he" just bought. "He" even happily singing Toni Braxton's hit song, "Unbreak My Heart," in an off-key tone. Darryl then has a serious "I just got screwed," expression on his face.
I got a little off track, but these are good examples of excellent acting and Isabelle nailed it! :)
It's like, cool. It's like, totally rad awesome!