"At Yahoo! Labs we design algorithms that are primarily driven by large scale applications for data mining and machine learning in a production environment. We

"At Yahoo! Labs we design algorithms that are primarily driven by large scale applications for data mining and machine learning in a production environment. We show that the S4 design is surprisingly flexible and lends itself to run in large clusters built with commodity hardware." Via http://labs.yahoo.com/event/99 http://labs.yahoo.com/event/99 I could've sworn there was a blurb there about where they are using and I recall using "real time map-reduce jobs" for things live bidding on ADs and such; another use case would be with stock market data. You're right that it's marketing speak, this project has gotten too much attention on HN in the last few days even when all the git repo had was initial commit. It's too bad they don't have proper explanation, maybe it's because they weren't probably expecting all this attention yet.