Of the highlights for the scheduler tree with the Linux 3.16 merge window are NUMA scheduling updates for better performance, CPU idle changes to improve the high level idle scheduling logic, standardized idle polling across architectures, and continued work on preparing better power/energy-aware scheduling. Another change to point out is for using the deepest C-state always when in the "freeze" sleep state.
The power-aware scheduling for the Linux kernel has been something that's been in the works for many months and is nearing fruition.
More details on the scheduler enhancements for Linux 3.16 can be found via the pull request. Ingo Molnar also sent in his perf, locking tree, and RCU changes for this next kernel cycle.