I thought we would find out more about Libby. All we found out that she is a widow and sold her husband's boat to Desmond. I want to know why she was in a mental institution. Think we will ever find out?
She didn't seel the boat, she GAVe the boat away, at least that is how I understood it. Seems to me that is the actions of someone who is going down the path of mental problems (if she isn't already there)
I thought it was interesting that her husband's name was David. Could she have Walt-like powers and have been projecting Dave to Hurley both in the hospital and on the island? Of course, it's also possible that she was used by Widmore to get Desmond out to sea and permanently away from Penelope.
I don't think there are any Dharma agents 'helping' people get to the island, the fact that the plane crash was a result of the button not being pushed in time indicates to me that there was no selection or plan for getting the losties on to the island, quite the opposite.