Apple's current method of switching between the dual Nvidia graphic chips in the new MacBook Pro is suboptimal at best. While Windows laptops with dual GPUs can discretely switch back and forth according to what the user is doing and if he's on his battery or plugged into a socket. Apple requires a manual switch accomplished with a log-off.
It was hard to believe that would stand for very long: it's the sort of cludgy solution Apple hates. And sure enough, Nvidia has confirmed with Gizmodo that the new MacBooks can indeed do on-the-fly GPU switching, they're just waiting for Leopard to catch up with the hardware. Better yet, the chips are also capable of Hybrid SLI, which might lead to a radical increase in gaming performance if Apple gets around to patching it in.
Gizmodo ends with a word of caution though: "But since it's Apple it's also entirely possible we'll never see any of this to come to pass–GPU-accelerated video decoding has totally been possible with the 8600M GT in the previous-gen MacBook Pros, and well, you know where that stands."