In trying the alternate search engines, I found that the results weren't that significantly different than a Yahoo or Google search. At the heart of the results of any search or information gathering will be credibility. And who is the ultimate definer of what that means? For instance, if we take the current situation in Iran, most of the "credible" or established journalists were being arrested, detained, or forced to leave the country. What the world is left with then is the twitter, fb and youtube postings from otherwise unconfirmed and perceived unreliable sources. But, the end user can read the posts, look at the pictures, watch the videos, listen to the chants, and ultimately make a decision. They don't need CNN or NBC to explain it to them. It's all right there.
Similalry, on a lighter note, TMZ broke Michael Jackson's passing. TMZ, which would be considered by most as tabloid at best.....but the lines get blurred when the information proves true.
A book I read recently, The Numerati by Stephen Baker, is a fascinating book about how our searches, tweets, and updates are being used to gather information about us as much as providing information. It is the storing and processing of this megadata that companies are hoping to better understand how we vote, how healthy we live, why we buy, or who we love.