How about THIS: Jacob WAS supposed to meet them at the cabin - because that's where Esau/Bad Guy/Black Shirt/Evil Locke/A-hole was being kept so he couldn't screw up the world. But, maybe after an off-island excursion, Jacob came back, found the ash disturbed, figured out that the poop was going to hit the fan, left a note/clue as to where he'd be and went off to wait for whatever was going to happen.
BUT - so far anyway, Jacob is like this all-knowing, god-like guy - so he's probably just waiting around to get stabbed. BUT, if he can heal other people, can he heal himself, too? Maybe he's Jesus. Or a combo-god made up of Egyptian/Jewish/Christian/Stephen Hawking characteristics and gets up from the fire and stops time and gives evil Locke a big wedgie and then starts time up again?
I mean, this is LOST, so I am SO confused - but in a totally good way - and I SO cannot believe we now have to wait until next season!!!!!!!!! Maybe it would have been better to just not see ANY of it - then get the whole thing on DVD and have a month long LOST party at the end of next season!!!