Het changelog is:
AMD has moved to the AMD Radeon™ HD 4000, AMD Radeon HD 3000, and AMD Radeon HD 2000 Series new driver support model. These updates will focus on resolving application specific issues and critical updates. The reason for the shift in support policy is largely due to the fact that the AMD Radeon HD 4000, AMD Radeon HD 3000, and AMD Radeon HD 2000 Series have been optimized to their maximum potential from a performance and feature perspective.
CERT recently approached AMD with information pertaining to what they believed to be a possible video driver vulnerability exposed by non-default settings of the Microsoft® Enhanced Mitigation Experience Toolkit (EMET). EMET is a security test tool that allows system administrators to create test conditions to validate correct behavior of system components or indicate potential weak points. The presence of an issue does not necessarily mean that this issue can be exploited in regular operation of a system. The default safety settings of the EMET do not cause the issue in question to occur.
The AMD Catalyst 12.6 beta driver for the AMD Radeon HD 4000, AMD Radeon HD 3000, and AMD Radeon HD 2000 Series is designed to resolve a possible video driver vulnerability issue and to minimize the occurrence of system crashes.
Note: The In-the-box AMD graphics driver that is included with Windows® 8 will include support for the AMD Radeon HD 4000, 3000, and 2000 series, and it will support the WDDM 1.1 driver level features. The AMD Catalyst driver for Windows 8 will only include support for WDDM 1.2 support products (AMD Radeon HD 5000 and later), and will not support the AMD Radeon HD 4000, HD 3000, and HD 2000 series.