According to Vik Singh of the Yahoo! BOSS team, the combination of Twitter and BOSS is a real time news search facility that can mash Yahoo news with Twitter topics. What you end up with is the most timely delivery of news you can get, certainly much more so than the likes of even Google News for example.
BOSS, in case it has passed you by, is the Yahoo! open search web services platform and stands for Build your Own Search Service. The idea behind BOSS is simple enough, to foster innovation within the search industry.
If TweetNews is anything to go by, then I would say it is working.
In his announcement, Singh describes it as being a way to boost Yahoo’s freshest news search results by basing them on how similar they are to emerging Twitter topics. This fixes the problem that those original results are not very relevant as they are ordered by timestamp only. Employing Twitter to determine authority for fresh content that is not yet linked is sheer genius.
"Freshness (especially in the context of search) is a challenging problem" Singh admits, continuing "traditional PageRank style algorithms don’t really work here as it takes time for a fresh URL to garner enough links to beat an older high ranking URL."