We learned that there is not enough vaccine on the island for Claire and the baby (if Ethan was telling the truth - which I doubt). Hmmm, nope we didn't learn anything from that.
We learned that Desmond is probably an Other - since he knew enough to take vaccine with him before running out of there. Now I am starting to wonder whether Henry is one of them or not? Looking "grubby" no longer means you are one of the Others, since they know how to clean up when it counts. He didn't have the standard vaccine bottle and syringe with him - which they never go far without, so it seems.
What if he is telling the truth? Nah! He knew exactly what he was doing getting Locke to be really mad at Jack. He is as good as Sawyer at the con!