Get ready. Facebook is about to change advertising.

Here's our prediction: Facebook will launch a new permission-based advertising model this winter that will begin monetizing its 30 million users. And the people who laughed at Mark Zuckerberg for refusing $1 billion from Yahoo, or last week a $10 billion valuation from Microsoft, will get it.

To understand what's coming, look at recent history. Facebook has done only three things to ramp up growth. First, it opened doors beyond colleges to the entire public. Second, it launched News Feed, which updates your friends any time you do anything. And third, it freed its platform to software developers who in turn created thousands of wicked cool widgets.

Facebook got buzz about the open platform, but we bet News Feed is the killer app. Think what the feed does -- any time you open Facebook, you get news updates from all of your friends and colleagues. Rather than have stiff editors at NYTimes or Slate tell you what's important in the big world, your friends do with photos, videos, and news from your own social world. This is what makes Facebook unique.

Now, this past week Facebook announced it will tweak News Feed with a coming app that sorts your friends into categories. You can set up personal friends, work networks, church networks, family networks ... and ... we bet -- trusted ad networks.

Why do we see this coming? Facebook has pressure. It's sitting on $38 million from investors and has not yet found a clear way to make cash on its base. The banner ads that now appear on Facebook have extremely anemic click-through rates, and advertisers won't sit still for online ads that don't pay off in CPC or CPA. Users, after all, aren't searching on Facebook like they are on Google; they're socializing.

So Facebook needs advertising, it needs it to work, and it will need a new model. We predict the ad model will be a play on News Feed, with a group of trusted advertisers who can reach you only after you give them permission. Zuckerberg's move will be brilliant. The ads will be targeted, but limited; users will have control; and hawkers won't clutter up the Facebook ethos.

Call it permission-based Google. Call it advertising with only the brands you want to see. Heck, call it Adbook.

This app is coming, and it's going to do exactly what Zuckerberg dreams: Create a social graph that replicates your real-world activity, this time, in the land of commerce.