I really don't think Texas needs another baseball team at this point. (Yes, I realize that geographically it's a huge area, but still).
I personally dislike the idea of the Eastern US getting another baseball team. Portland really should get one, although I think MLB likes to leave them out there as a sort of red herring. "Your city won't pay to build a stadium? Fine, we'll move them to Portland, where they've been begging for one for 30 years!"
Las Vegas will probably never happen, since that will automatically make people second guess game results there.