It is an oft overlooked area of graphics cards, but driver quality can have a huge effect on the level of performance that can be coaxed from your shiny new hardware. Certainly with the release of Windows Vista a lot more customers will have become familiar with just how badly immature drivers can affect the stability of an operating system. Things are even more difficult in the open source community, any Linux users among you will no doubt be aware how notoriously hard it can be to get a graphics card up and running using the vendor-supplied drivers on Linux.
Historically, nVidia has always had much better Linux drivers, but AMD's latest announcement looks set to change that because the company is opening up the source code for public consumption. Better still, not only will the existing Catalyst release be available for tinkering but AMD has also pledged to make a full set of documentation available to enable budding coders to build 2D and 3D from the ground up - tasty!
All being well, this could mean that AMD will be able to get all the benefit of nVidia's "The Way It's Meant To Be Played" program. This will mean fixes for problems with specific games, which AMD developers can possibly shoe-horn into official driver releases, but without the overhead of actually doing all the testing itself.
Considering Linux is showing up on the radar an ever-increasing amount recently it isn't going to hurt AMD to make this move. Moreover it can't realistically effect sales negatively (AMD doesn't sell drivers) and could even lead to an increase in uptake from Linux users. Obviously, Windows users should benefit from this as well and the desire for open source content on that notoriously closed platform is growing too. Whatever the long-term effects of this announcement, one this is for sure: AMD won't begrudge a little positive PR, which its been sorely in need of recently.