Er, I believe Mexicana are going to be the next to join oneworld, as has been reported previously.

http://www.oneworld.com/ow/news/details?objectID=14804

Or are we hypothesizing as to the next one after MX? If that's the case, then I think VN could be a welcome addition in SE Asia, but an African partner, such as Ethiopian might help fill some gaps. I also wonder what Etihad and Qatar are up to, and whether they will both continue the 'go it alone' strategy that Emirates has adopted, rather than joining one of the big three alliances.

The thing about OW is that they seem quite selective as to who they accept as new members, preferring to find new partners who complement the existing alliance, as opposed to Star which appears to be happy to take anything it can get it's hands on and hope that the toes of the existing partners aren't treaded on too much.