The huge delays in the release of Microsoft Dynamics NAV 2009 was a result of Microsoft's "restructuring" of they development teams. For a number of years it was like Microsoft had almost eliminated most of the core NAV team in Copenhagen. It was very clear to both partners and users, that Axapta was the product Microsoft had their focus on now. Only a hand full of old NAV team was left.
But then in 2010 it was like Microsoft again put NAV in focus.
(The role center of NAV 2013)
Dynamics NAV 2013 was released on September 28th, 2012. The name of the role-tailored client, is changed to the Windows Client. The classic client is no longer available, but FINSQL.EXE still used as the "Development Environment".
RapidStart is the old rapid-imlementation tool, but now changed so much, that it actually became a very good tool for use in data migrations. It is no longer need to write special dataports or xmlports to import data.
The release also contained many new application and development improvements. And in many ways, then NAV 2013 was what most partners had expected NAV 2009 to have been.