Some of us have started a blog where we will post useful information related to mental ray and Maya.
The blog will focus not only on the artist's needs but on some tips from developers as well.
This will provide you with easily understood concepts. The aim is to provide better understanding of rendering methods, tools, and actual studio practices. For now this will lean towards VFX work (since the thrust is Maya) but we hope it will be useful to everyone.
Any suggestions you have are welcome as well as ideas for concepts to cover or integrate into other topics.