The media don't report stories with a bias, but they also define values. And this happens in the journalism, not just on the ad pages.

In the UK you can't buy a Sunday paper without it being full of special features about glossy stuff you really want to buy, and stories about people who are famous and rich.

Occasionally there may be some cutesy throw-away feature about people with different values, or other people with unfamiliar lifestyles (not always through choice.)

But the main emphasis on 'lifestyle' is constant and reliable.

Changing media ownership rules might not modify that.

It's certainly true that the Murdochs of the world shouldn't be allowed to have the power they have now. But as long as you have centralised media there will be pressure towards on-message conformity.

The best you can expect is a reliable diversity of messages in the mainstream, instead of a monoculture.