I just read the last part of the Announcement. It will boost sales that are generated from pages. They will be able to generate money from the search engine just like google does. The difference is that it brings in results spacific to the likes of you and your friends. This means you are more likely to pick on the same things and buy the same things as your friends.
Mark didn't dumb it down for everyone so it may take a day for it all to sink in. He is one step ahead of everyone once again.
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