Also, S1 out on DVD tomorrow? How is this the first I've heard of that?
Okay, first thing is that everyone is so very in character. Ted frustrates me with his refusal/inability to let go (though I have to admit I would probably feel the same way -- though Ted is so tactless) but it's entirely consistent with who we have seen him to be.
Dude, Robin on Doc (of Disney's Seven Dwarfs) "He went to med school, what's he doing hanging around with six coalminers?" She overthinks things even more than I do. Which feels potentially a little bit out of character, but I think it's not. (Robin's probably the character I have the most difficulty getting a handle on.) Her reticence about personal stuff is absolutely in-character, though.
I kept expecting her to nearly break up with Ted because he wouldn't let it go.
I can absolutely see her blurting out that she's married because to deny Ted's/Marshall's suspicion would be to let them win -- to not be entitled to her privacy. But to have such detail at her fingertips? That screams girl-who-spent-obscene-amounts-of-time-p
We've already seen her slipping into romantic/commitment at times (her "I never said 'never,' " hell even her sitting on the roof with him back in "Slutty Pumpkin") and she recognizes that she's got a great thing in Ted ("Ted Mosby, Architect"), so I'm actually okay with "You know me better now. It feels kind of nice."
The one false note in the episode was "I just turned thirty" as one of Barney's "oh" moments, 'cause he's all about bagging the desperate chicks, and we had an entire episode about him and attractive older women.
Other good things:
I loved Lily's deadpan "Try me" (re: the whole they-tell-each-other-everything thing).
Barney: Your hand is monstrous.
Marshall: Yeah, well, what'd you expect? You've seen my penis.
Of course you wanna take the ten right now. And we have another potential running (or at least recurring) joke.
Edit: fox1013 has lots of good stuff from the episode.