This was quite an episode tonight; I have to admit I'm still processing it but I wanted to share some observations.
First, the wine: I wasn't expecting this to be the device that gives Jacob his power/responsibility, but the scene got me thinking. It seemed that as children, Jacob and MiB were 2 sides of a coin, one dark and one light, each incomplete in his own way. For instance, the young Jacob seems incapable of lying. When Jacob's mother gives him the wine to drink, she tells him, "You're just like me now." Now, the wine was used by Jacob as a metaphor for evil, darkness, etc. in Ab Aeterno. Perhaps it's more than a metaphor; what if Jacob had to drink the "evil" wine in order to balance his "inner scale", to make him capable of doing whatever is necessary to fulfill his role as protector? Jacob's scale still remains more to the good, but perhaps in order to be able to understand evil and combat evil, he had to take a little "evil" wine into himself. For me, this adds new depth to the scene from Ab Aeterno when he gives MiB the bottle; it always seemed to me that Jacob was taunting MiB in that scene, now even more so. Jacob can understand the duality of human nature in a way his brother cannot.
Now the light spring. I liked that they tied the island's mysterious EM pockets in to the spiritual mystery of the island. My guess is that the Temple was built to protect that spring, and that the healing waters emanate from it. The mother's warning about "taking too much" fits well with Dogen's meticulous timing of Sayid's immersion. MiB's transformation to the smoke monster confirms that he is definitely connected somehow to the island EM energy, and leads me to question what Desmond's role will ultimately be.
Finally, the unfrozen donkey wheel. I loved seeing it being built, and it just made me see how long MIB has been trying to leave, and that the FDW was always a major part of his plan. I'm led to wonder who actually completed it; I imagine many different visitors to the island, pawns in the game, with MiB/Smoky manipulating them to complete the wheel, which MiB so needed to be able to create his loophole.