This was already mentioned in the last developer meeting notes, but I think it merits its own post: the Blender Foundation has changed the licence for the Cycles rendering engine from GPL to Apache. Other tools can now include Cycles as well, and the BF believes that this will help it grow.
Brecht van Lommel writes:
As of today the Cycles source code license has been changed from GNU GPL to the Apache License version 2.0. This is a permissive license that allows Cycles to be linked and used with any program, including commercial software and in-house software at studios.
The design and purpose of Cycles always has been to work as an independent and reusable rendering engine. When Cycles was added to Blender two years ago, we decided to release it under GNU GPL first, specifically to ensure it would develop into a well integrated production rendering system for Blender. With that target to be established well, it’s now time to find out how Cycles could work outside of Blender too.
We hope this move would help Cycles grow as a project in the long term, as the project could attract more contributors and might be easier to use for studios under the new license. With the release of various libraries by movie studios like OpenEXR, Open Shading Language, OpenSubdiv, PTex and OpenVDB, which we use or plan to use in Blender, we also think it would be
nice to contribute something back under a similar permissive license. As Cycles is reasonably stand alone and integrates many of these libraries already, it’s a good candidate to share similarly with everyone.