It didn't really make for a super exciting episode, but it did help set the scene for The Ponds departure which is really sad.
I think they are possibly the first companions that you see really consider leaving The Doctor at least in this way and you see how they manage their time with The Doctor and at home. More so than with the other companions in the new series, you got the idea of how long they were gone when they were living "Doctor Life."
To me the episode was dull, because the boxes took so long before they actually did something. I was almost as bored as the Doctor on a few occasions. (I think I might have nodded off 20 minutes in for a few)
Overall this episode is just another disappointment for me. There are three great actors and they are being utilized so poorly.
Oh and story arc? This one is so bleh....