We (Eclipse PMC) have been discussing migration to Github so we try to get closer to the bigger developer community and at the same time enhance the tooling we use daily.
We have prepared a document  listing why, what, when, how according to our best knowledge but we are looking for your comments, ideas, etc. so together we choose the best path forward for Eclipse IDE development process.
P.S. All communication channels are fine - comments on the document, mailing list discussions and even calls to discuss things.
Red Hat Eclipse Team