Michael Jackson owns ~50% of the publishing rights to most of the Beatles songs, which is not the same as ownership. Jackson's attorneys have some latitude in negotiating mechanical license rights, but he can't actually do much about Apple Corps selling their songs. It's worth a lot of money for him though.
However, my interpretation of the situation WRT Apple vs. Apple is that the out of court settlement itself suggests that there is something interesting happening. In the past two court cases, Apple Computer has lost to the tune of less money than it costs to fly Steve between meetings. Over two decades of litigation. Apple can afford to leave this to rot in court, then pay the expected penalty of a few tens of millions. There are a couple of orders of magnitude difference between wealth from computers and music.
So what is happening here is possibly a smokescreen for Steve to spend some of Apple's cash surplus without being chastised by the shareholders. It's likely to be good for Apple, and its likely going to be awesome for a couple of musicians and a couple of families of musicians.
Think back to the meeting between Jobs and Sony. Allegedly this was in relation to iTMS, and apparently Sony didn't buy in, although neither company wishes to comment. Sony is the other ~50% of the publishing rights of Northern Songs, and presumably handle the tedious side of the business Jackson isn't interested in.