Hm, has anybody thought of that: Jeremy was a potential hunter and now IS a hunter – one of “THE FIVE”! Why? Because – magically – every random boy out of about seven billion people on earth becomes a potential / hunter – or, because it is some gene passed down the Gilbert family line … They have made a bit of a fuss about hunters – about them having to be male or possibly female? What if Elena has is a Doppelganger ( thanks to mother’s family line ) and in addition to that “burdened” with a gene that would make it extra difficult for her to become a vampire ( what with some kind of “hunter’s gene” ) … No siring bonds needed here! Damon’s heartbreaking decision might have something to do with passing or not passing on certain information he might or might not get in New Orleans … ( I don’t know if he would be capable of doing anything that might end what will obviously start between Elena and him after everything he has been through – A man can only take so much, right? )
Maybe it is all about Elena being human or vampire – although it sounds a little bit “constructed” to me …
Nina Dobrev has spoken about it several times: What’s a person like? Who fits better? So: Who is Elena? And which brother would be fitting more?
Elena WANTS to be human … If that would mean she’d be back to being with Stefan again … What would Damon do about that?
And: Has anybody had a look again at those portrait cards with the Latin sentences? Actually I am pretty convinced that in Stefan’s sentence the Latin grammar is quite wrong – would that have a deeper meaning? And as for Damon’s sentence: It would rather mean: “The guilt is part of the blood” – not just “blood is guilt” … and – from what I’ve found in the different dictionaries – “reatus” might even mean “condition / status of the accused” ( Like: The condition of the accused is due to the blood” … would open some more doors to possible interpretations )
The swords that point at the heart above him seem to look like those which are embossed on Tyler’s paper frame.

And Elena’s card: Two circles beyond the portrait leading in two different directions … Above the portrait: A heart, embedded in two triangles of the same size … the flames of the heart parting into two different directions and the sentence saying: ( she is ) bound / held by ( the ) blood – and blood dripping onto one of the circles – blending it out a bit …

Oh, but I would agree, that her description of her feelings for Damon at the end of the third season (“consumes”) was pretty strong …

Yeah, I don’t know … I’m getting a headache … ;)

 Elena is not sired to Damon. There is absolutely nothing that points to that, as a matter of fact going into episode 7, it is not even feasible that would be the case.  If Elena was sired, Stefan would have been attacked by her when he vervained Damon and took his day walking ring.  Elena’s behavior is not that of being sired, but instead she is finally accepting how much she loves Damon.

The sire thing would be a crock and would tick a lot of people off because it would be just another tease that something was going to happen only to have it be taken away. I don’t really think the sire thing will happen unless it’s a desperate attempt on Stefan’s part to keep them apart. Still it would be discounted pretty quickly because of her previous conversations with Matt before she turned. Unfortunately it’s not Nov 29th. Too bad we don’t have a time machine. :)

If there’s a way to give all three a happy ending I’m all for it. And even though I’m super excited to see Damon and Elena together, I’m positive that this isn’t the real end of Stefan and Elena and that’s not a bad thing.

 OR maybe we love this show and have come to the conclusion that nothing is ever what it seems.  Just when the show is headed one way they surprise us and go another way.  They wouldn’t have made it such a big deal if it was nothing if it was the same as Caroline drinking they wouldn’t have said anything .

I haven’t had time to read all the comments, so I don’t know for sure if anyone’s mentioned that in the books, vampires can’t have sex. They do things like blood exchange instead.
In the Nightfall book, Stefan and Elena are kissing, and it gets so passionate that they start floating, and blood sharing. This is from the book (edited a bit): “And then there were no more words, only feelings. … And so they slowly spired up in the moonlight … until they reached the top of the tree.”
I loved that during Damon and Elena’s blood sharing scene (in the show), the song lyrics were “I want to feel like I am floating.” So frigging perfect for how I imagine it feels. Anyway …
Damon is sitting in a nearby tree and sees them. This is from his point of view:
“… they had started their love scene. … Floating up to his level and caressing and more. … He’d had to grind his teeth when Stefan had offered Elena his blood. Had wanted to scream that there had been a time when this girl … the taste of his blood would make her reach heaven in his arms. … Elena had wrapped herself around Stefan … and had fastened her mouth against his neck, as Stefan’s face had tipped toward the sky, his eyes shut.” That’s what Damon did in the show. :)
In an interview, Julie Plec said that the blood sharing scene between Damon and Elena is “a little bit of a shout-out to the books, but also just to vampire folklore in general. If you look at any of it metaphorically, it’s a very intimate exchange of bodily fluids.” … “So you can read into that what you will.” … “It’s like vampire naked cuddling.” She laughed. …  It “doesn’t come with any side effects.” Hope that helps a little. :D … It’s snowing! First snowfall of the year for me here in southern Canada.

 I love your post. Finally someone who wants to do the guessing games instead of daydreaming about Delena.
The Hunters-gene could be in the Gilbert Family and although Elena has different parents she is still the daughter of a Gilbert. Maybe she has the Hunters-gene, too. So she is a potential hunter and a vampire at the same time which might cause a conflict and stop her from being a normal vampire who can drink any kind of blood.
And the more I think about this Hunters-story and the cure the more it seems wrong. The more vampires a hunter kills the more of the tatoo map appears and the map leads to a place where you can find a cure for vampires? So why do they have to kill vampires only to cure them later? That makes no sence, does it?
This hunter who lured Rebekah into his bed knew about “special vampires” (originals) and he knew he needed the ash of the white oak and the silver dagger to stake Rebekah. I’m sure he also knew it wouldn’t kill her forever. So I assume he wanted to kitnap Rebekah. But why? Maybe the map leads to some place where they have to do a ritual for which an original vampire is needed?
And why did April’s father kill himself and the council people? Was he a hunter and activated knew hunters by killing himself? Or did he know about the ghostworld and this was a way to transfer to that world to fight on the other side? Maybe Professor Shane helped with that.
About Damon’s heartbreaking decision. We know that the episode is about a flashback. Maybe this decision happened in the flashback. Something like Stefan going to war and Charlotte staying in New Orleans and Damon had to decide between the two of them?

 Amen.
I do think that there a points to it though – but also facts that underline the possibility of siring. I guess it is their intention to mislead and we have seen some foggy moments and gaps in the past. So I really don’t know what to think. If you watch only this last epsiode in regard of the siring possibility, it could be true. There were a lot of incidents underlining this theory. In the long run on the other hand Elena’s feelings for Damon are undeniable there. So my guess at the moment is that the plan is that Elena indeed is sired to Damon and that their coping with it is the quest they have to solve the rest of this season.