I've discovered that my MacBook Pro 17" (late 2009) has screen issues that have also been plaguing other owners. I have a screen flicker that is easily noticeable on this very journal page:
It can be hard to see on a small image like the one shown above, but is very easily noticeable on a large version of the image, especially when it is moved to the lower part of the screen.
On the "better battery life" option for video performance (when the MBP uses the NVIDIA 9400M graphics card instead of the NVIDIA 9600M GT), I see visual artifacts when scrolling in applications like NetNewsWire. So far, that's the only application I see artifacts in, but I suspect that there are artifacts in others as well. The artifacts go away when I switch to the 9600M GT.
I tried installing Apple's recently released MacBook Pro Graphics Firmware Update 1.0 for early 2009 17" MacBook Pros, and discovered that I'm already running that version of the firmware. Fail.