Canon has released firmware updates for its range-topping EOS 1D Mark III and 1Ds Mark III cameras. The updates, to versions 1.2.3 and 1.1.2 respectively, provide new custom functions to provide direct access to autofocus points and additional ways to apply exposure compensation. They also promise to: "improve the stability of AF accuracy in AI servo AF mode when shooting extremely low-contrast subjects."

1D Mark III users also gain additional control over wireless Speedlights (which was included in 1Ds firmware at launch).

Further details can be found here:

Canon 1D Mark III

Canon 1Ds Mark III