This is what review I typed while watching the episode for the first time. So not all of my thoughts are in there, just what I felt like writing at that moment. I'm lazy and posting this now instead of watching the episode again and writing more - I bet I'm gonna be annoyed at my laziness later. But whatever. You can has review:

Ooh, interesting recap! Does that mean we get some backstory? The title seems to say that too. :oD
What, Ruby got herself a Cool Car?
Ooh, does Dean get a vision of the future now? Or is he in the past? Everyone has a Cool Car - OMG, is it really the past? Lawrence, Kansas! \o/ OMG, I'm so excited! Just over three minutes into the ep and I'm already squeeing. I know, it's nothing new but: I love this show! Dean asks where he can get reception for his cell and dude says USS Enterprise, hee. Oh, but dude is not John, right? I mean, it would be totally freaking awesome, but so weird! I'm not ready for more awesome just yet. "Sonny and Cher broke up?" ^^ Ah, dammit, if I knew when those two broke up I would be able to tell a bit better exactly where when Dean is. Okay, the big question is: is this like a dream, most of it really happened like that, but the interactions with Dean are made up by his brain? Or is this like he's really in the past? Ha, imagine he meets John and/or Mary and they they name their first son after him! XD LOL. News Paper Dating! Oh, it's still 6 years till Dean's birth. Bwahahaha, it's John! I am so in love with this episode. I think we're gonna get married and have a kid, name it after a stranger we met. Anyway, Dean's stare, heh.
"So what, angels got their hands on some DeLoreans?" XD ...but if you ask me, judging by Castiel's clothes, more like TARDISses. Holy shit, so this is really real? :O
Stop it? Don't tell me, he has to stop his parents from meeting/falling in love (to prevent Sammy from ever existing). Would be funny, but also so totally fucked up - and as soon as he succeeds he stops existing. Of course then the question is how he could get back in time if he never existed...which is this complicated wibbly wobbly, timey wimey thing again that always tries to break my brain.
AGENT SKINNER IN THE CREDITS! WOOT! This episode is getting more awesome every minute. I knew he'd be on Supernatural - that was the spoiler I tripped over some weeks ago.
"That's not the one you want." says Dean, leaning on the Impala. AHHH! Dean helped choosing the Impala? \o/
"John Winchester." says John and I am so, so curious what Dean will say his name is. Ha, of course he says Dean (because he has to be named after himself), and a rockstar name XD. Never was an alias so cool. Because really, how often do you get to use it on a journey back in time?
Mary! \o/ "Mom is a babe." Oh Dean, that surprises you? Where do you think you got your super mix of pretty-genes from? "I'm going to hell." Oh Dean, you perv XD!
HOLY SHIT, MARY KICKS ASS! Dean's ass! XD ... :O She was a hunter?
Oh god, please let Mitch Pileggi be Mary's dad! ... OMGYAY! :oD Sam and Dan's grandpa is Agent Skinner! Um, guys, have I told you how much I love this show? Ha, grandpa's name is Sam! And, ooh, there's grandma! Deanna, haha, I so saw it coming! Aw, Mary named her kids after her parents!
LOL, grandpa dressed as a priest...and Dean too. Senior senior priest Father Cheney - not McCain? Ahem.
Charlie says that the demon said something about 10 years and only then I realized that it's 10 years before Mary's death! Yellow eyes! But why is he doing CRD stuff? Oh, god, I hope Mary doesn't summon the YED in an attemp to get him and he forces her to make a deal.
"You know the worst thing I can think of, the very worst thing, is for my children to be raised into this like I was." makes me cry. And Dean too. OMG. Dean makes Mary promise something (and he and I are crying some more) and we all know she won't remember. And it's really time I mention this: great casting! You can really see that's Mary. There's something in her eyes that I recognize from Samantha Smith.
Campbell! Mary has a last name! Finally!
Dean tells grandpa the truth and he says he believe's him, but the way he's looking at the Colt makes me think he wants to take it and shoot Dean. And then he even asks to see the Colt! OMG, it's the YED!
OMG, I never expected to see the YED again! And there he is, OMG! Okay, it's not Fredric Lane, but hey, it's Mitch Pileggi! So is that's what it is about, what they want Dean to do? The angels wanna know what the YED's end game is? Whoa, does this mean his death was just the beginning?
Hey, the Impala's plate isn't KAZ 2Y5 :o( - they could have brought it back here! *sigh*
Wait, WTF? The YED killed John! :O ...Maybe that's the deal Mary's making, she gets John back. Ahahaha, I just realized that John came back from the dead too - long before Sam and Dean did it. It's family tradition ^^. Ew, incesty smooching. You know what that was? It so totally was fanservice, in a way...because that's the only incest they'll ever give us.
Isn't it scary in how many ways history repeats itself in this family?

Okay, stuff I have to mention, but don't know where to put without watching the ep again:
1. Dean learns about the YED dripping blood into the chosen babies's mouths and it isn't all that interesting I think. Because what I only noticed later is that this is one of the secrets Sam is still keeping. This info is new for Dean...and he still doesn't know that Sam knows.
2. Sam. Yeah, he didn't get a lot of screentime. But I'm glad we saw him at least once, because really, we couldn't have an episode without him. That would be just wrong.