This is first time when Apple has added support for non-mac graphic cards as reported by 9 to 5 Mac. Now, early 2011 Macbook Pros support the AMD video card through Mac OS X 10.6.7 software update.
According to Tony, Apple has included a graphic acceleration for some AMD/ATI Radeon HD 5xxx and 6xxx card. The following graphics seems to be supported :
1) ATI Radeon HD 5630 Device ID 0x68D8
2)ATI Radeon HD 5630 Device ID 0x68D9
3) ATI Radeon HD 5670 Device ID 0x68D8
4)ATI Radeon HD 5730 Device ID 0x68D8
5)ATI Radeon HD 5770 Device ID 0x68B8
6)ATI Radeon HD 5850 Device ID 0×6899
7)ATI Radeon HD 5870 Device ID 0×6898
8)AMD Radeon HD 6850 Device ID 0×6739
9)AMD Radeon HD 6870 Device ID 0×6738
10)AMD Radeon HD 6970 Device ID 0×6718
No information on why Apple is using these PC graphic cards but it is considered that the company will implement most of them (not all) in the next iMac update. This is a pretty new thing for those who have just upgraded Mac OS X to the latest software as it also include Sandy Bridge kernal for new Macbook Pros.
[via 9 to 5 Mac]