MALEV, TAM, and CSA have codesharing agreements with Air France, and if I am not mistaken, MALEV has another one with Delta. In the future, I see MALEV and possibly CSA and TAM joining the alliance. TAM would be a good addition to the Skyteam Alliance, as it is one of the only large South American airlines left that has not joined the a major alliance. However, they have some agreements with American, which may create some conflict.
I would not be surprised if Thai tries to leave the Star Alliance, as it is to be somewhat privatised soon and the buyers could come from anywhere. The Skyteam airlines should and in my mind will try to buy into Thai, as it would also be a good addition to the growing alliance.
I don't think JAL will decide anytime in the future whether to join an alliance. However, it is correct to say that it is close to Oneworld, as it has agreements with American, Cathay Pacific, and British Airways and its franchises. It does, though, have a frequent flyer agreements with Air France, which it has had for a long time.
Emirates has been reported to be considering Star for a potential partnership, so I do not think it would join Skyteam.
Alitalia is a possibility, as it has lost agreements with one of the main Wings partners (KLM) that it would cooperate with if that alliance ever materializes.