I've got at least a "hello world" for R / Arrow bindings in progress. https://github.com/clarkfitzg/Rarrow
Over the next couple weeks I plan to spend some time looking at the Arrow C++ and Python sources and write a few bindings by hand, then think about how to automatically generate bindings from the C++. Several approaches are possible, Rffi / rdyncall, Rcpp modules, or RCodegen / RCIndex leveraging Clang. Not sure which, if any, will work. I'm a beginner in C++. It would be very helpful if someone was available to answer questions on the C++ Arrow codebase, since I'd rather not email the whole dev list for this. Thanks, Clark