Preface ... Why we watch
When Season 1 started, I'll admit it, I passed on Lost. By Season 2, I found myself playing catch up and soon became an addict.
Why? Well, the storyline, intelligence of the writing, and the acting all rocked. Those are obvious reasons. But let's not forget one of the most important factors: the casting.
As a straight male, I can't help but note the female cast. As much as Kate's character annoys me, she IS drop-dead sexy. Sun is one of the most underrated beauties ... note that she has perfect lips. Claire and Juliet, well, blondes always get my pulse going.
For the girls, I hear no complaints about Sawyer and Jack. Dez has got the accent. And Ben ... just kidding.
Alright...the theory
Short and sweet. My bet is that there will be no replacement for Jacob. Now, I don't read spoilers...ever. So, maybe some of you can prove me wrong by something leaked from the show. I have no idea. But based on episodes only, I think that Jacob and MIB are both currently tasked with protecting the island. Mom had been the protector. All three have murdered someone (Fake Mom offed Real Mom, MIB offed Fake Mom, Jacob essentially offed MIB).
Jacob is dead, and MIB is a little bit dead and alive. Lots of people are banking on Jack as the next island protector, but I think the protector must have the ability to be deceptive (which made MIB, mom's best candidate). Jack is not a deceiver or a murderer. If there was a replacement, I'd bank on Sawyer: he has murdered an innocent and is pretty awesome regarding long cons. Same thing with Ben.
But I think Jacob has already said what will happen when he stated, "It only ends once." And I think we already saw the result at the start of Season 6: a sunken island. I also believe that the actions (sacrifices) of the Losties on island will be followed by a flash to the group of key characters at the hospital (a place of healing) in the Sideways world.