The useR! conference will be held at Stanford University on June 28 and 29. This sold out conference has quite a few tracks and a lot of sessions. The sessions cover the gambit from intro to expert. I think anyone can find a session or two of interest regardless if you are new to R or an expert. Topics are varied and you can find sessions on performance, tools and applications of the language. Microsoft will have sessions on their new language support in Visual Studio.
This year Microsoft’s Channel 9 will live stream the keynotes and speaker-permitting will record the sessions. Soon after the session, those who were not able to attend, should be able to view the session on-demand. Check Channel 9 for more details: https://channel9.msdn.com/Events/useR-international-R-User-conference/useR2016