The service, said Adam Swidler, a senior manager with Google's enterprise group, "brings the reliability of Gmail to Microsoft Exchange users."
Google Message Continuity is being offered by Google's corporate e-mail service Postini, which also offers security and archiving services.
Citing a 2008 Radicati Group study and a 2008 Dell Modular Services study, Swidler claims that Microsoft Exchange users experience an average of 2.5 hours of e-mail outages every month and that 72% of companies must deal with an unplanned e-mail outage annually. The Radicati Group's research suggests Gmail is 10x more reliable than Exchange when planned downtime is taken into account. (Gmail doesn't have planned downtime.)
Inaccessible e-mail costs organizations money, an annual amount that Osterman Research puts at $178,170 for a 1,000 person company.
The cost of insurance, in the form of Google Message Continuity, comes to $25 per user per year or $13 per user per year for existing Postini customers.
Swidler says that while Microsoft offers its own disaster recovery and backup service for Exchange, Google Message Continuity costs about half as much on average.
Google Message Continuity is the latest in a series of Google services designed to lead enterprise customers away from Microsoft's on-premises solutions toward Google's cloud. Swidler calls Message Continuity "a service that offers a bridge to the cloud." Other such bridges -- a better metaphor might be siege ladders that reach up to Microsoft's office windows -- include Google Cloud Connect, Google Apps Migration for Microsoft, and Google Apps Sync for Microsoft Outlook.
Swidler says that Exchange 2010 support is something Google will consider. But right now, he says, Google is focused on companies using Exchange 2003 and 2007 because they have a more urgent need for a disaster recovery and backup solution.