Yammer - corporate microblogging

David Sacks, author of the Geni genealogy website, launched a new project called Yammer . Yammer is essentially a corporate Twitter . The main slogan of Twitter is the question “What am I doing at the moment?”; In Yammer, the user answers the question “What am I working on right now?”. Yammer is intended solely for corporate use. Like Facebook, at the initial stage of its development, Yammer only requires internal email addresses to register users. Unlike Twitter, Yammer has its own business model. Although the service can be used by employees, companies reserve the right to independently manage users, their messages and rights.
The service is now available online and ported to AIR, iPhone and Blackberry.