Nvidia seems to be pushing "Modern" OpenGL as an alternative to Mantle:
http://www.dsogaming.com/news/nvidia-talks-opengl-offering-massive-cpu-performance-boost-via-modern-opengl/
http://de.slideshare.net/CassEveritt/beyond-porting
http://www.dsogaming.com/news/nvidia-talks-opengl-offering-massive-cpu-performance-boost-via-modern-opengl/
http://de.slideshare.net/CassEveritt/beyond-porting
