Today, Apple pushed an update for Mini DisplayPort equipped MacBooks across the board. The update addresses issues that users who purchased the Dual-Link DVI adapter and actually tried to use it. They also improved the playback of HD video with the NVIDIA graphics in each of these machines. The press release follows.
About NVIDIA Graphics Update 2009
This update improves cursor movement when using the Apple Mini DisplayPort to Dual-Link DVI adapter with the Mini DisplayPort enabled MacBook Air, MacBook and MacBook Pro.
It also improves playback of HD video running on systems with NVIDIA GeForce 7300 GT or GeForce 9600M graphics.
To update your new MacBook, select Software Update from the Apple menu. A restart is required.
Via [Apple Support]
sadly nothing is fixed with this update. when changing the graphics card to "high performance" an external apple 30" monitor display is not even recognised. when changing back to "better battery life" the display is recognized sometimes but only renders highly distorted images. tested with two current macbook pros 15" 2.8ghz and two different mini display port to dual link dvi adapters on two different 30" apple cinema displays. apple should recall this adapters!