[baguasquirrel]

They are agreeing on a protocol, they aren't saying that they're going to share their mined and ranked data. No way in Hell is Google going to agree to that.

My bet is that Google is worried about its relevance in a world where an increasing amount of the data is not accessible to its crawlers. This is not just FB and Twitter, but Yelp and GroupOn traffic as well.

That's where Yahoo and MSFT come in. By agreeing to standardize search APIs, they can hope to net more of the developer mindshare. Now, instead of this just being "lets program for Twitter or FB's or Google", this becomes "lets program for one of the social networks, or for search". Google doesn't lose the monetarily valuable human-driven search results, and YHOO and MSFT get to take a risk that they will be able to monetize potentially valuable developer-driven search along with Google.

The thing that's funny about this is that no one seems to have figured out how to monetize APIs yet. If anyone is going to figure it out, it may well be Twitter because it is life or death for them. But Buzz goes to show how much Twitter envy there is going on at Google. They're concerned that if there is a way to monetize that traffic, then they will be shut out. Better to take a larger share of the pie with YHOO and MSFT than for traditionally-crawled to get shut out of the party.