In recent information provided to Tom's Hardware, AMD will be moving the AMD Radeon HD 2000, HD 3000, and HD 4000 series of products to a new driver support model. AMD will be supporting these graphics cards through its Catalyst releases, but they will be moved to a quarterly basis versus the standard monthly updates. The Radeon HD 5000 and newer products will continue to see the monthly updates through the Catalyst releases. The quarterly Catalyst releases 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 Radeon HD 2000, HD 3000, and HD 4000 Series have been optimized to their maximum potential from a performance and feature perspective. The 8.97-based driver, to be released in May, will be the first driver for the Radeon HD 2000, HD 3000, and HD 4000 Series under the new support model. According to AMD, it is an extremely stable and robust driver branch for these products and will be the baseline for the quarterly updates. In an effort to optimize the Radeon HD 5000 and newer cards, AMD states this move is the best use of its resources, as the Radeon HD 5000, Radeon HD 6000, Radeon HD 7000, and future products have the greatest potential for further performance and feature enhancements.
As with regards to Windows 8 support for the AMD Radeon HD 2000, 3000, 4000 series of products, AMD states that the in-the-box AMD Graphics driver that ships with Windows 8 will include support for the AMD Radeon HD 2000, 3000, and 4000 Series. In addition, 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 newer graphic cards).
You can download the latest AMD Catalyst drivers here at AMD's website.