celgins - 10:12 pm on May 18, 2011 (gmt 0)
A lot of folks in this forum are thinking about this with only a webmaster's mentality. And I can almost guarantee you that the masses don't think like webmasters.
Microsoft is simply following a social trend that has been dominating the web for several years now. There are millions of users who want to know which movies their friends think are cool. They want to know which restaurants have good ratings, and whether or not their sister, cousin, or mom would eat there. They may also be interested in news events, videos, music and articles their friends are exploring.
I'm guessing most engineers and webmaster/developer/SEO-types could care less, but webmaster/developer/SEO-types don't dominate the web--users do. And it's the user who seeks to share, discover and socialize, and Microsoft is taking a stab at making its SERPS more social.
There is a reason why sites like Urbanspoon, Yelp and TripAdvisor have become so popular. Some people, instead of making a unilateral decision, would rather get tips, pointers and perspective from others. It's all driven by a desire to be less wasteful with their money, to explore best practices, and to discover the exciting and unknown. Now, more than ever, it is much easier to do this (through social networking, mobile applications, etc.) and Microsoft would be nuts to ignore that audience.
Will it work? Who knows, but webmasters won't make that decision--users will.