In the flash forwards:
Hurley doesn't have millions,
Jack's dad is alive, and
Kate didn't blow up her step-daddy (and her first love is alive and with her now).Oh yes she did!
The island is a conduit amongst realities. The past two episodes may be suggestive.
We know that the future is exactly what we have seen. How they get there is the mystery!
Yep. I liked this "new past" idea about as much as anyone - but 4x04 killed it. Everyone can point at Kate's act of murder - in the past, on the island, after the island, and even after the island remembering before the island. You're right, Jug - the path they take is the mystery.
Hey, Puff, why don't you WRITE a story about that erased past? It's a great idea.