Jon, you're very good so I look forward to your results. A comment on fps would be nice. Looks like the monsoon is finally finished so I have sun, probably too much, for the next 6 months so the D300s should work fine. I am primarily interested for my young son. He has a D200 and uses the D300 but at nine a lighter and , in some ways, simpler, camera would keep his progression in photography moving forward. He gets discouraged with the iso limits on the D200. If the AF is decent I could always borrow it for early/low light mornings at the Pond, an extra stop would be nice.
Hopefully by the time I start thinking about the next monsoon the D400(?) will be a reality and time for my wife's semi-annual London trip (Grays of Westminister ). Cheers, Tom