Please find below the list of new features introduced since SQL Server 2005, 2008, 2008R2 and SQL Server 2012 (it will be a very long blog post!).
If you're interested in attending an event to learn more about SQL Server 2014, we've created a consolidated view of upcoming events, including the Microsoft vision for IT Infrastructure.
This list also includes some technologies that work together with SQL Server such as Azure, System Center, Excel 2013, Power BI for Office 365 and others.
Please find information how to upgrade to SQL Server 2014 here.