Very close friends. Steve and Yao stayed in touch even after Steve was traded. NBA wise, Steve is probably Yao's best friend.
Sorry to quash an illusion! I don't think that Yao Ming and Francis have much in common, outside of their profession. Yao Ming gives the impression that he just isn't one of the boys, he isn't even trying to, nor is he the man about town! If you live with chinese people as I do you will know what I am talking about.
Thought it was Boki? TMac and Yao's relationship seems pretty good as well. The Jimmy Kimmel show appearance comes to mind.
They are still very close at least in the players' locker room, as their lockers are just next to each other.
http://sports.sina.com.cn/k/2007-10-19/11533235083.shtml And in the above Chinese article, it mentioned the following scene that I'm not sure any of you guys noticed watching the game from TV. (I did not as I had not the chance to watch this game live from TV). The writer said during the 2Q, while the 3 of them were watching the game from the bench, Steve Francis was sitting in the middle with Yao Ming on his right hand side, and Tracy McGrady on his left hand side. And during the half-time intermission, both Yao Ming and Tracy McGrady stood up and pulled Steve Francis up from the bench with their hands. And when Steve Francis got up from the bench, Tracy let go of his hand, but Big Yao just walked towards the changing room together with Steve Francis with his hand cuddling on Steve Francis' shoulder. The writer continued to say to Big Yao, regardless what happened to Steve Francis, whether he is starting, or just serve as a back-up, or even lock up into the dog house, Steve Francis will still be Big Yao's Lao Da.