All good points Scott. I would add...
1. Charlie being so possessive of both Claire and the baby is marginally acceptable as he has shown to have an addictive personality. At the same time, I think his jealousy, which has come on suddenly, was a bit overdone.
2. I agree completely. He still has the love of his life back here in the US. However, I would only add that his declaration of love for Shannon is probably a strong indication of his believing that they will never get off the island.
3. Given their volatile personalities, I would have thought anyone of the three guys would have told her to shut the f up. I too am surprise at how willing they have been to take her crap.
4. Whispers have been heard many times throughout Season 1, but this is the first time they have been directly associated with the Others.
5. Even if they saw the dog, I still think the B word would have shot Shannon. Ironic that she admonished Sawyer, et al ealier in the show ("One bullet will do nothing against them," or something like that), yet she was pretty damn quick to pull that trigger herself.
I'm leaning towards the possibility that Shannon lives, and that other chick is gone for good. We shall see.