Upcoming graphics hardware will definitely go down the blue road, but at this point we don't what will be the major difference between DirectX 11 and DirectX blue. Both Nvidia and AMD are working on DirectX Blue chips as we speak, but they are still quite a long way off.
Using such a codename for Windows is nothing short of ironic, due to Windows blue screen conotations. Also, it brings back fond memories of a famous Redmond demonstration that made Bill Gates even more popular. Of course, the USB printer demonstration failed and ended with a blue screen, in front of some rather amused members of the press.
In any case, DirectX blue is the future of graphics and it is coming in 2014, or perhaps even later.