Perhaps "what are you searching for?" Messages posted and available to read through that interface will be to and from your Google Contacts. (That's the people you Gmail with, basically.) Google is making a big push for people to take their Google Profiles more seriously and one consequence of that could be a well populated social graph for users.
Friends could help answer the questions you're asking of Google or they could let you know what they are doing, like a home town version of Google News.
Test Pilot is sort of a distributed usability lab. It uses simple crowdsourcing mechanisms to gather data from volunteers all over the world as they interact with web apps and desktop software. The collected data remains transparent and openly available, so the data sets can be used by anyone.
By donating your bookmarks, you let GiveALink analyze your preferences along with those of many other people. We will mine the resulting collection for interesting insights and use the information to develop novel applications. We will also share bookmark data with the Web research community, hoping to foster the development of many novel Web mining techniques and applications to search, recommendation, navigation, personalization and visualization of the Web.
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