Neil Gaiman's previous episode, The Doctor's Wife, was one of the best episodes the show has ever produced. Unfortunately, while his return episode was entertaining it was also very flawed and featured as many moments of idiocy as it did genius.
Firstly the positives. The new look Cybermen were fantastic - a brilliant melding of the new series Cybus Cybermen and the original series Mondasian Cybermen. Gaiman was also pretty successful in his attempt to make the Cybermen scary again - the moment where one moved at super-speed was a fantastic reinvention of an enemy that usually gives you days' worth of warning as they slowly clank towards you.
Jason Watkins and Warwick Davies were both brilliant, if underused. Sadly time that could have been spent exploring their roles was wasted on an army unit of buffoons (they certainly were a Punishment Unit - every scene with them hurt) and two of the worst child actors I've seen in a long time, who all felt like they'd wandered in from a very different, and much worse, show. Warwick especially shone - I'm hoping his character makes a return appearance as there's certainly more of his story to be told.
Jenna-Louise Coleman felt like she was playing a different role this week - whoever she was she certainly wasn't the Clara we've got to know over the last half dozen episodes. She has apparently also gone blind, at one point asking The Doctor where the children were when they were clearly stood less than a foot behind him!
Matt Smith (who was also playing a different role this week) was amazing as a villain - his range seems to improve from show to show. He certainly shouldn't worry about being typecast when he decides to leave the TARDIS (hopefully many years from now). Unfortunately what should have been the focus of the episode was often pushed aside in order to show characters, who we had little reason to feel sympathy for in, in jeopardy.
two of the worst child actors I've seen in a long time, who all felt like they'd wandered in from a very different, and much worse, show
All in all, it was a fun episode, featuring some brilliant performances from the adult actors, and a few interesting set-pieces - the moment when the Cyberman factory activated and thousands were unleashed deserved a better episode to showcase it. But sadly, it was a fairly generic episode that could have been written by anyone, so much so that I felt a little bit let down by Gaiman. He's such a talented, original, imaginative writer and after his brilliant debut last season this was a bit of a disappointment - Nightmare In Silver was very much the runner-up of his episodes.