SharePoint Workspace 2010 provides a Groove Web Services API that is compatible with the API in Groove 2007. The Groove Web Services API allows you to develop an application that can access data in Groove workspaces and tools.
Your application runs in its own window, and you can design a user interface tailored to the needs of your users. In many cases, users access the Groove data exclusively through your application and do not need to use the SharePoint Workspace user interface. This allows you to focus your development effort on meeting the needs of your users, while letting SharePoint Workspace handle the task of replicating the data to all the members of the workspace. Note that the SharePoint Workspace 2010 application must be running in order for your application to access the Groove data.
The Groove Web Services SDK for SharePoint Workspace 2010 provides sample code, documentation, and WSDL definition files that provide access to the Web services API.
If you’ve written an application using the Groove Web Services APIs available with Groove 2007, you can run them on a SharePoint Workspace 2010 installation after making minor changes to your application. SharePoint Workspace 2010 encrypts the Groove Web Services request and response keys with DPAPI encryption before storing them in the registry. To port your application from Groove 2007 to SharePoint Workspace 2010, you need to modify the code that reads the registry keys. See the release notes on MSDN for details.