I agree Derek - the D300 is almost as good with high ISO but the D3 has the edge - This is a D300 - ISO 3200 shot -
http://www.worldphotographyforum.com/gallery/showphoto.php?photo=29680&cat=500&ppuser=2724
- D3 still to be tested by me in this area but all reports suggest it will be better and your cycling shot holds the promise. By the way Derek - you've kept very quiet about the new camera.
Stephen I think the D3 AF secret is that the sensor now has some "intelligence, subject recognition" built in. I think this is what may make it appear more responsive.