Originally Posted by smcclelland 
The example you posted is a common problem with any AF system, even my 40D and 1Dmk2n suffer the same fate with objects traveling towards camera (it's a depth perception issue) and Nikon's D300 and D3 have the same ordeal. The only alleviation I've had with this is strapping a 2.8 or faster lens (either the 120-300 Sigma 2.8 or the 70-200 2.8) on the 40D and using its increased AF mode with center-point. So Ben if you're reading this, put the bug in Pentax's ear about objects traveling towards camera with AF
I have seen pretty good results from the D3 with objects travelling towards the camera.
One I remember was a dog doing some slalom run directly towards the camera, the guy had 7 out of 9 frames correctly focused IIRC.
So somebody can do it, the thing about the D3 is the complexity of the focus settings, trust me it is massive, so getting it set up correctly will seriously affect the results. I have spend 2 weeks with my D3 and I have not even come close to finding out how to get the most from the AF system... but initial results looks decent enough.
Not bashing anything, but the D3 and the 1DIII (that is what I have heard anyway) both seems to pull it off, but again it is a completely different market they are aimed at.