According to this article from TCPalm.com, Jim Crane is looking at the possibility of moving the Astros' Spring Training facilities from Kissimmee out to Arizona, but is also exploring the idea of sharing facilities with another team in Florida.
The latter idea - which is used in Arizona - has been previously mentioned. Crane toured the Mets' facility in Port St. Lucie (which is a mere ten miles from The National, the golf course Crane owns) last March. As early as December 2011, Crane mentioned moving from Kissimmee once their agreement ends with Osceola County Stadium in 2016.
Way back in August 2010 the Nationals expressed interest in moving from Viera to Kissimmee, where they could share facilities with the Astros.
Crane, on the two-team facility:
"We think the economics work for whomever wants to do it. One, you can keep the costs down. Two, you've got more activity there. And we've been told it also works really well because you can play that other team, too. It just makes everything better. That's what you're seeing in Kissimmee."