I finally was able to get caught up....
I actually like the finale. As for as killing off main characters, there are few shows that kill of their main characters. Most of the time the actors that play the main characters sign a contract, for most shows it's a three year contract to be renewed. Sometimes it's longer or shorter, but you can't just kill them off (have them disappear for a while is different). Personally I didn't consider Jeremy a main character until now.
As far as the show, I do not find it far fetched considering they have a witch who may be able to bring someone back to life, and if she can't in most cases all they have to do it get V blood into that person before death takes over. They actually did kill of a main character Vickie, but it seems she's now back as a ghost but for the past year she's been MIA and dead. Jeremy- someone said that his character had no point (something like that), maybe his character will change and he will have a much more instrumental role next season. Well, we know the Bonnie brought him back (at a cost she was warned of), they can do a lot with the ghost thing. I read the books quite some time ago (before show), and none of the main characters were killed off in them either. Now I admit that this show is nothing like the books, usually that irritates me, but it gives the show the chance to make things unexpected, and I do like that. I wouldn't peg Jeremy as the new "Ghost Whisperer", I don't see his character going that way, especially since it seems he is seeing dead vampires, not humans (which may change)....in fact I wouldn't count on knowing where they are taking this show. Yes, I figured Jeremy would be brought back in some way, it's a supernatural show after all. As for Stephan, sure he'll come back and it will probably be Damon and Elaina that get him back. But, how much damage will Stephan do in the mean time? & How close will this search bring Elaina & Damon? Don't cross your T's yet bala, I think things could get quite interesting.
OH, and I happened to love how John gave his life to save Elaina, that was something I did not see coming and I certainly did not think John would ever act so selfless.
Also, I did not see Stephan being forced to drink blood a mile a way, not until Klaus brought up Stephan's earlier killing spree and even then I wasn't sure how Klaus was going to get him to join him. The drinking of human blood was a genius idea, it spiked Stephan's cravings. However you can tell by Stephan's attitude (after he comes down from his blood high), that he is still somewhat in control and biding his time, yes he killed that girl. I'm sure he knew that both she & he would be dead if he didn't (by Klaus).