Microsoft Business Productivity Online Standard Suite is a set of messaging and collaboration solutions hosted by Microsoft, and consists of Exchange Online, SharePoint Online, Office Live Meeting, and Office Communications Online.

+ These online services are designed to give your business streamlined communication with high availability, comprehensive security, and simplified IT management.
+ Take a case, for a customer who need more than one standalone service, the Business Productivity Online Standard Suite provides the best value to customers by bundling multiple services at a discounted price.
+ Microsoft Online Services are accessible through a variety of mobile devices including Windows Mobile 6.0+, Exchange ActiveSync devices, and BlackBerry devices.

For more information, you can get more information from the following articles:
http://www.microsoft.com/online/business-productivity.mspx
http://smallbusiness.officelive.com/en-us/email