After a handful of episodes devoted to resolution of various plot threads, this stand-alone installment is a bit jarring. Not because it is bad, per se, but because it's not necessarily the best use of the time the show has left. Some have claimed that the past few episodes were evidence that the writers hadn't quite finished out the season before the cancellation notice came down, but this episode suggests the opposite. (Someone, I'm sure, has the facts straight.)
This is another Keller-centric episode, and that will inevitably annoy the fans who dislike her very presence. I would like to think that Dr. Beckett's return would mitigate some of the negativity, but somehow I doubt it will be enough. I'm not sure that was the problem. Despite some nice (if confusing) ties to the overall Stargate continuity, the episode just didn't offer very much (with the exception of Jewel Staite in leather, which is hard to complain about).
Having Keller switch bodies with a hot young thief was somewhat clever, since it placed her in a dangerous situation, but I'm not sure it did much to advance the character. The experience didn't inspire Keller to demonstrate some hidden depth or a dark side or any of the things that might have made the Freaky Friday situation a bit more interesting. In fact, with so much time spent on the guest star, there wasn't time to push the envelope with Keller.
It's a pleasant enough episode, in the end, so it's not going to offend too many people (other than, perhaps, Radek fans). It's just not the most energetic or original episode, either. It's fairly average. That wouldn't be a problem if this were any other time of any other season, but this is the very end of the final stretch. The net result is that it will seem, to many, like a waste of potential.