if Apple were to release an iTV it would obviously run the same OS as the

TV. It makes sense to continue beefing up the OS in preparation. Especially if Apple wants to make an app store for the iTV. Now there are millions of

TV's all over the world that will give a greater incentive to devs. Can you imagine if apple said "Ok devs, start making some apps for this $1,500-$2,000 tv that I'm gonna be releasing in a few months. I have no idea how successful it'll be, but give it a shot!"
People go where the apps are, apps are built where the people are. If you start out at zero it's kinda tough to get either one.