It's a good rumor, but would be stupid.
Apple needs to enter contracts with all of the media suppliers to make its products and services attractive. Owning Disney would make Warner, Sony, Fox and the rest nervous about dealing with Apple.
It's an ideal arrangement right now. Apple knows what Disney is thinking. Disney's board is open to making deals with Apple.
Also, look at AOL/Time Warner. It seemed like a good deal at the time with lots of synergy. But the fact remained that it operated like different entities - there remained different cultures, different fifedoms, and the company was too big for people to meet others in the opposite side of the company. It divided the focus of upper management. It was a bust.
Then look at Sony/Columbia Pictures. They remain the smallest of the big media companies by quite a margin. They have not been nearly as aggressive as the other big media companies, since top management is more interested in electronics and games than movies and TV.
It's much cleaner if Jobs can be on the board of Disney and think only of entertainment. When at Apple he can focus on devices and their services. Deals are only done when they make sense for both entities.
I doubt that the deal will happen. And if it does, it will be lamented in three years time.