David Talbot of Technology Review has posted an article about the ranking of real time search and Twitter with the help of Amit Singhal who is a lead engineer at Google. See below for a quote from the article:

“The tweets are a mainstay of Google’s real-time results, but Google has not previously discussed how it ranks them. A fundamental Google strategy for identifying tweet relevance is analogous to that used by Google’s PageRank technology, which helps find relevant Web pages with traditional Web search. Under PageRank, Google judges the importance of pages containing a given search keyword in part by looking at the pages’ link structure. The more pages that link to a page–and the more pages linking to the linkers–the more relevant the original page.

In the case of tweets, the key is to identify “reputed followers,” says Amit Singhal, a Google Fellow, who led development of real-time search. (Twitterers “follow” the comments of other Twitterers they’ve selected, and are themselves “followed.”)…..”

Related Links: Technology Review Article