doubleofive said:

The on-Island stuff is OK, but the flash-sideways stuff brings up too many new questions/storylines that they have no time to resolve them all. I'm very eager to see how it all ends without disappointing us all.

That's why I'm feeling more and more like they're related more tightly than we think. My current theories are:

1) It's all one timeline, we're just looking at two different sections of it (like in Ji Yeon, with the simultaneous flash-forward/flash-backs. They all go back to the island in 2007, and end up where they are now, but they just took a different path to get there. As Eloise pointed out to Desmond, the universe has a way of course-correcting.

2) The two timelines complete each other. This thinking came from this excellent blog post, which references quantum entanglement:

"Quantum entanglement, also called the quantum non-local connection, is a property of a quantum mechanical state of a system of two or more objects in which the quantum states of the constituting objects are linked together so that one object can no longer be adequately described without full mention of its counterpart -- even if the individual objects are spatially separated in a spacelike manner."

Intriguing.

3) After last night's episode, I'm wondering whether The Man In Black is going to force the integration/crossover of the timelines. When he was offering Sayyid the opportunity to get back what he wanted -- was he offering to bridge the timelines and restore Sayyid to his "current" state in the new 2004 timeline?

Thoughts?