From the player, to his agent, to Chelsea, everybody keeps saying the same thing. Petr Čech may not be playing much, and everybody may realize just how weird and, shall we say, inconceivable that is, but it would appear that he's unlikely to change employers this January. Čech wants to only play for a top club, his agent realizes that goalkeeper openings at such clubs aren't exactly plentiful, and Mourinho simply wants the veteran around as his safety net.
"The most important thing is what he brings to the team on the pitch, which is top quality."
"When Courtois was injured against Arsenal and Petr Cech comes to play on minute 20, I was so calm. I wasn't worried about a change of goalkeeper. So when you have on the bench a super goalkeeper like Petr Cech this is the most important thing."
"Obviously he wants to play, which is why sometimes I make him play. I have to feed the natural ambition of somebody who feels he is a top goalkeeper."
"I have to feed that ambition to keep him... I'm not saying happy happy, because to be happy a player must play every game... but at least to make him feel that we like him, we respect him and we need him."
-José Mourinho; source: Yahoo! Sport
Čech's been a model citizen throughout this whole paradigm shift, and by all indications, he's been a great mentor and even friend to Thibaut Courtois. All in all, we're pretty lucky that this situation hasn't blown up in our faces and has worked about as well as we could've ever hoped. Come the summer, Petr will most likely get to move on, but until then, we'll get to continue to enjoy having the best backup goalkeeper in the business.