SharePoint Server 2013 has been optimized for the way people work, providing people with a familiar, consistent view of information, collaboration, and process, and IT with a comprehensive, easily-managed and integrated platform to meet the needs of the business.
New features of sharePoint 2013
Business Connectivity Services
Business Connectivity Services offers improvements to the way that SharePoint 2013 and Office 2013 clients can access data that is stored outside of SharePoint. These improvements include support for apps in SharePoint, external list improvements to provide functional parity with other SharePoint lists, and support for OData Business Data Connectivity (BDC) connections. Visual Studio 2010 can connect to an OData endpoint through business Connectivity Services to automatically generate a BDC model for OData data sources. There is a SharePoint 2013 event listener and subscriber to receive notifications from external systems when data changes.
SharePoint exposes list data via OData.