Daleks defeated by a Mcguffin button, very bad.
Saving the earth, good.
Tardis pulling the earth across the universe, cringe worthy bad.
Fake regeneration, lots of talk to hook folks into episode.
Fake regeneration, plays havoc with established understanding. Doctor 10, 10.5, 11? I dunno, is Matt Smith then 12? Regeneration hands for all = huge plot hole for future writers.
Lots of companions, good.
Companions going suicidal and acting out of character (Sarah Jane and diamond, Rose's mom toting guns), trying to make a point of the Doctor's army just didn't seem to work well for me.
Donna reverting to her old self, tragically good.
Dumping Rose again with kissy stuff, just awful and undermines the season two finale. Once is enough!
The Stolen Earth, good.
Journey's End, sorry but this one ended up bad. Why can't finale part two ever be as good as finale part one?
Please don't let the upcoming regeneration special start off great, but then part two goes all "situation suddenly solved in 5 minutes, soap opera for the remaining 60 minutes of episode".