Hi all, (This concerns Mac users only; the rest of you do not need to read this.) When R-3.1.0 is released on April 10 you will notice that there are two flavors of R available for download for the Mac: a version built on Snow Leopard (Mac OS 10.6) and a version built on Mavericks (Mac OS X 10.9). The Snow Leopard version of R will work fine on all versions of Mac OS X from 10.6 onward, including Mavericks. Binary Bioconductor packages are NOT yet available for the Mavericks build of R. The two versions are not binary-compatible. If you install the Mavericks version of R, you'll find that you are unable to install Bioconductor packages with biocLite(). You should be able to install packages from source, but this will require that you have a development environment set up, and various system dependencies depending on the packages you're trying to install. This is not recommended. What we do recommend is to use the Snow Leopard version of R. With this version, you'll be able to install Bioconductor packages with biocLite() in the normal manner. We have ordered some new hardware to facilitate building Bioconductor packages on Mavericks. After the hardware has arrived, we'll set up builds on it and verify that they are working properly. At that time we'll make an announcement on the Bioconductor and Bioc-devel lists, and you will then be able to use the Mavericks version of R with Bioconductor. Thanks and please let us know if you have any questions. Dan