1)Another pivotal episode, as we finally get to see Amy decide where her priorities lie, whether with the Doctor or with Rory, which is good, because that whole storyline was beginning to be a bit wearisome. We also get Rory's first "death", starting hom on his way to becoming the "Kenny McCormick" of Doctor Who.
2)The Dream Lord is an interesting character - sort of a re-invention of the Valeyard. I've noticed that's kind of been a sort of sub-theme that Moffat has brought up from time to time - the Doctor's inner darkness. "There's only one person in the universe who hates me as much as you do." That's pretty dark. It is kind of weird watching what is effectively the Doctor tormenting himself.
3)Having old people as villains is amusing - you can't trust those oldies, they're always up to something. The fact that the nursing home was called "Sarn" was intereasting, though sometimes I think that they throw in these references just to give us aging fanboys something to chew on.
4)Some fun quotes:
An interesting story that holds up to re-watching - the Dream Lord is an interesting baddy that I wouldn't mind seeing again. Some good emotional moments in this as well, particularly where Amy only realizes what Rory menas to her when she thinks he's gone.
[Part of list of Doctor Who episodes here.]