The data tables that Apple publishes for its recent machines imply that the underlying support for better OpenGL display port functionality is included in the system. But maybe Apple's driver implementation is still too incomplete or unreliable.

http://renderingpipeline.com/2012/06/mac-opengl-capabilities/ [renderingpipeline.com]
https://developer.apple.com/graphicsimaging/opengl/capabilities/ [developer.apple.com]

Chronon
The data tables that Apple publishes for its recent machines imply that the underlying support for better OpenGL display port functionality is included in the system.

Included in the system doesn't necessarily mean usable. See also:
http://renderingpipeline.com/2012/04/sad-state-of-opengl-on-macos-x/ [renderingpipeline.com]

The second bullet (Core profile only) is biggest reason why Houdini can use GL 3.2 on Linux and Windows but not on the Mac.