Linux 4.0-rc5 Mostly Has Routine Driver Updates
Linux 4.0 brings many changes and numerous features though at this stage of development the work is just about fixing bugs/regressions. Linus noted that 4.0-rc5 has roughly the same amount of changes as 4.0-rc4, but it's mostly the usual driver updates and other non-exciting changes for this late in the cycle.
For the current Linux 4.0 state there isn't anything too scary except for a NUMA balancing performance regression that is still being worked on by upstream developers.
More details via the announcement of Linux 4.0-rc5 on the LKML. I'll be out with some new Linux 4.0 kernel benchmarks shortly.