The code name of the next new major release of Microsoft Dynamics AX 2012 is Ranier, which will be released in fourth quarter of calendar year 2014. (Dynamics AX on Cloud in addition to on premises offering)
The Microsoft Dynamics AX 2012 R3 will be released in fourth quarter of calendar year 2013.
Regular Cumulative Updates (CU) ill be released every quarter.
Read Microsoft Dynamics AX to deliver Windows 8 apps in 2013; Major release ‘Ranier’ due in 2014 by
Source: www.MSDynamicsWrold.com