It looks like they spent a fortune on that episode. The aliens were pretty well realised and there were a lot of them.
It had a lot of interesting ideas, even if the weren't wholly successful. I can see this dividing opinion, I give them full marks for trying something different but take one back for the resolution.
Good stuff with him sneaking back in time to check out Clara's past to try and figure her out and her starting to twig to it.
Really? I thought it looked like they'd badly stretched the budget, none of the aliens even had faces that moved. The sets really limited. There were some interesting stuff that didn't really seem to hit properly. And to be honest the whole thing with Clara is grating. What is it with Moffat and the obsession that the companion has to be special, and the Doctor will have known/seen them through various parts of their life? Amy, River (in a round about sort of way), Reinette, now Clara, it's annoying.
Personally I would say so far I'm enjoying it more than last series but there are some things that really are bugging me.