Yes, I had mixed feelings about it myself. It was a clever, well-written episode but it lacked the heart that some other, less-well-written but more enjoyable stories have.

It also overlooked another implication which is inherent and unstated in the Dr Who mythos. What were the chances of the Doctor randomly being on the one tourist bus that was attacked by the un-named entity? The most logical reason would be that he attracted it himself, since its ultimate goal was to absorb his intellect and use it. So yet more deaths happened because he was around.

This isn't the first time the Doctor's interest and prsence has brought danger with it. The Daleks punched through time and space to Canary Wharf precisely because that time and space was the most likely to find "time travellers". Everything that followed with Cybermen and Daleks, right through to the events of the recent Earth-stealing finale, followed on from the Doctor's frequent visits to "his favourite planet".

But that aside, the episode managed to be spooky and horrific and set up the moment of "soul exposure" in the finale fairly well. It'll never be my favourite, but it was well done.