You guys know that there's a whole conference dedicated to real-time rendering, right? Go ahead and take a look through the papers from this year or last year and see how many come from academia. I would also suggest reading through the history of PRT research, or Ravi Ramamoorthi's long history of frequency space rendering if you want some examples of research that goes beyond just "implementations". Another good place to look is any of the many recent papers focused on using spherical gaussians and other SRBF's for representing BRDF's, NDF's, and visibility functions.
Besides...it's not like any research that isn't specifically focused on real-time rendering means that it's only exclusively relevant to offline rendering. Real-time rendering often makes use of the same techniques, principles, and insights as offline rendering. This is especially true if you factor in things that are pre-computed offline for use in real-time applications or games.