Here are some things I have noticed about Lion and the 9400M GPU:
- Launchpad animations are fairly smooth when your computer is plugged into an outlet. When your computer is not plugged into an outlet, however, the animations are horrid and will make your system feel ancient.
- I'm not sure why this occurs, but Launchpad animations are smoother when it is accessed from a fullscreen application. For those who don't believe me, try it. It's very strange.
- Mission Control animations are decent. I have noticed, however, that when no windows are open the 'zoom out' animation is smoother. When multiple windows are open, the animation stutters.
- All animations are somewhat degraded when driving a high-resolution display.
The animations on Apple's new machines are buttery smooth and I hope that, with future updates to Lion, we are able to enjoy that buttery smoothness too.