JCT-VC is working on the successor of H.264
The Joint Collaborative Team for Video Coding committee (JCT-VC) has collected a number of improvement proposals for the next H.26x video encoding standard, the successor of H.264.
In Dresden, Germany, 15-23 April a number of Universities and public media company like MIT, Toshiba, Sony, Nec, Sharp, Intel, JVC, DoCoMo, France Telecom, Microsoft, Samsung, BBC etc. have presented their own proposals for improving the performance of H.264. However the definition of a next international standard (H.265?) will require many years. Remember that H.264 specification was finalized in 2002, and after 8 years it has not been yet fully exploited.
If you are curious about the proposals, I suggest to read the individual presentatons here. Very interesting, although it is a very technical reading.