This blog is updated daily.
A general description is here.
There is a new function ‘assignInMyNamespace()’ which uses the namespace of the function it is called from.
The ‘clusterExport()’ function now allows the specification of an environment from which to export.
When checking examples under more than one sub-architecture, ‘R CMD check’ now uses a separate directory ‘examples_arch’ for each sub-architecture, and leaves the output in file ‘pkgname-Ex_arch.Rout’. Some packages expect their examples to be run in a clean directory ....
The preferred toolchain has changed since the one used for R 2.12.0 to 2.14.x: see the‘R Installation and Administration manual’. Compiled code (except DLLs) may be incompatible with previous toolchains (and compiled C++ code almost certainly will be).