That's not to say that Apple has switched sides, as the company employs Nvidia chipsets and GPUs across the entire MacBook, starting with the GeForce 320M in the 13-inch MacBooks to the GeForce 330M discrete part in the MacBook Pros.
This could be a sign, however, that Apple and AMD are forming a stronger relationship. Earlier this year, rumors did the rounds that Apple may be considering using AMD CPUs in its upcoming computers. LINK