I didn't like Planet of the Dead or the Next Doctor, but I liked Waters of Mars (save for two points, which I'll get to later). I like that Doctor Who is full of whimsy, but the first two specials were to the point of overload, so that's one reason why I liked Waters. The Doctor's very own nature and raison d'etre helped increase the show's mythology, but the interplay between him and Brooke were such highlights that pushes the show from the maligned term "kids show" to family show, and quite beyond in a mature way.
(also, a point of contention: complaining that the setting seems cramped is kind of silly, seeing as how that's the point in making cramped settings - it heightens paranoia and claustrophobia, reinforcing the point that the colonists are trapped and in grave danger)
Now, the two things I didn't like:
-the usual overuse of music: the BBC released a few preview trailers without music, but I recall the lack of music really helping to drive the creepiness (case in point, the scene where Brooke and the Doctor find a crewman assimilating another in the garden was super-effective without music)
-the Doctor's breakdown at the end: yes, I realize it had to happen somehow, in order to push Brooke and for RTD's intended end-show goals, so I can forgive its necessity. How it was executed though, seemed really out of character, artificial, and overwrought for Ten. Yes the Doctor is arrogant, yes he's powerful, but the way he quickly and rapidly descends into believing his own mythology seemed psychotic without much explanation as to why or how he got to the breaking point (esp. for a character whose usual MO is to always come up with the right plan at the last moment).
