Apple and HBO will join together to provide contents through Apple TV.
Regarding this Bloomberg says:
Cable and satellite subscribers who pay for HBO will be able to watch more than 600 hours of films and television shows on Apple TV, said the people, who asked not to be identified because the talks are private. Apple TV is a set-top device that streams content purchased on iTunes and via other online services to consumers’ televisions.
It seems that the HBO content will be arriving in the set-top-box in the first half of 2013.