Long answer: It's probably not going to be a big priority amongst those who will be capable of programming for the Apple TV once it's jailbroken.
Getting the Bluetooth stack up and running will be hit and miss- it may *just work* or it may not. Expect to pay for it, though, as that's how the cookie crumbles in Cydia world.
As Safari is effectively already on the new Apple TV (in its iOS incarnation) then it's probably just a GUI away from being turned into a usable browser.
I wouldn't bet on any of this happening any time soon, though. But you're welcome to try your hand at some hackery yourself.