Lots of changes, and more on the way.

Here’s one of four core principles for today’s media market: these days, talk is cheap.

It’s a simple idea. Take a lesson from Uncle Buffett and his acolytes at Morningstar: your castle is only as good as its moat. If others can easily invade your market, it’s a bad business.

Expressing an interesting opinion is relatively easy. It requires intelligence and skill, but not a lot of work or time. Yesterday, therefore, it was doled out as a reward to people who had already put in lots of work and time.

Today, no such aristocracy exists. The cleverest, hardest-working opinion makers rise rapidly to the top.

This, of course, is why TimesSelect didn’t work: interesting opinions aren’t scarce. And it’s the oldest cliche in the Valley of the Newsosaurs: blogs are interesting but empty.

Hey, most of them are.

But here’s something that many commentators don’t appreciate about local information markets, as opposed to national ones: local information is useful. Local information tells me where to apply for a job, where to go for fun and where not to walk after dark.

In a world where only the most relevant information gets read, media outlets need to be useful.

Usefulness requires work and time. The work can be in filtering, packaging or reporting. But whether you’re an ink-stained newspaper reporter or a greasy-shirted blogger, work and time are almost certainly going to be your moat.