I'm liking Amy a lot, but I did feel that she came off a little too smug in this last episode. It was the sort of attitude that ended up putting me off Rose. It certainly wasn't enough to put me off Amy, as I thought she had some good moments, too. Not quite sure exactly what it was, but I didn't feel she worked as well as she had in previous episodes.
I also think it was too son for her to save the day again. Although the reasoning was very sound (that she understood human emotion better than the Doctor) it just seemed a touch too much focus was placed on her, being that she has now saved the day two episodes in a row. Conversely, I loved the "there's always a blue wire, or is it red" "you're not helping" moment.
But I liked her a lot in the previous two episodes, so I'm not going to knock her on a somewhat sub-par part in this last episode. To be honest, I won't judge her (or Matt) fully until this series is complete. Until then we won't know what is bad acting, bad scripting or intentional story arcs.