Here are some OSX benchmarks from the 680MX. These numbers are very solid and essentially beat out the Windows equivalents with the exception of the transition from DX11 to OGL in the Heaven bench. Again, if people were expecting 3DMarks of 8000 with the 680mx, there appears to be a large amount of growth on both OS's for driver maturation.
Heaven (Native resolution, default settings.)
FPS: 38.7
Scores: 974
Min FPS: 24.4
Max FPS: 95.9
LuxMark (Sala default, GPU only)
Samples/sec 814K
Rays/sec 7840K on 488.5k tris
Geeks 3D GPUTest (native resolution, default options)
FurMark
Score: 1916 points (FPS: 31)
GiMark
Score: 3623 points (FPS: 60)
For comparison as well, here are the numbers from the 2011 HD 6970 under Win7. As you can see, this alone shows that the OpenCL drivers in Win7 for the 680mx are very immature as even the last years iMac beats the performance of this years 680mx.
Heaven (Native resolution, default settings.)
FPS: 26.4
Scores: 664
Min FPS: 15.3
Max FPS: 50.9
LuxMark (Sala default, GPU only)
Samples/sec 492K
Rays/sec 4749K on 488.5k tris
Geeks 3D GPUTest (native resolution, default options)
FurMark
Score: 1161 points (FPS: 19)
GiMark
Score: 2602 points (FPS: 43)
Glad I could help folks. Now everyone enjoy your machines as they start trickling in over the oncoming weeks!