The whole idea of Dinosaurs on a Spaceship definitely had a great gimmick to it, but I found the extra characters a bit disconcerting (with the obvious exception of Brian Williams); mainly due to the fact that they had no prior character development, and we're just supposed to accept that they're friends of the Doctor. Granted the Doctor meets people on his adventures that we don't see, but throwing these characters into a televised story where you've got a very strict linear timeframe to tell the story in just doesn't give time for the audience (or me at least) to really connect to them on any emotional level, which is a shame because they were sure entertaining.
It was an issue shared by AGMGTW last series, a group of people that the Doctor knows which we don't; I could argue that it was worse in that example because of it being the mid-series finale, with so much to focus on plot wise, that many non-established characters just hindered the plot... it's not like we saw them again later in the series (though I hear Madam Mc-Silurian ... her name escapes me at the moment
will be returning in this years christmas special). So I guess there's my more of a review, thoughts?