Hello,
This would need the Wine Expertise of DirectX reimplementation as well as some good kernel hacker, but in the end maybe the struggle to have linux specific support from Graphics adapter vendors could be one for all removed if we had LDDM driver support and then and X build on top of it (same philosofy as Xgl).
I haven't looked at the tecnical side of this, but while support for LDDM drivers might bring the advantages above, it also has drawbacks:
* It might be a part of Wine functionality that is limited to Linux. * It will always be limited to X86 and X86_64 architectures only.
The Linux graphics driver situation is not bad, in my opinion. The nvidia driver is good, some say it's better than the windows driver. The ati fglrx driver's quality isn't that shiny, and I have a lot of problems with it, but it's getting better and better. The intel graphics chips have Open Source drivers, as do the ATI radeon chips, and the nvidia chips(2D only).
The bigest problems are Linux specific graphic functionalities, like Xinerma, and Windows drivers will never ever help with this - Look at the ndiswrapper project, it will never be able to provide a master mode, because ndis doesn't support it. One thing that could improve is the 3D acceleration speed, but I doubt it will be much better. Take the ATI cards: The Linux driver is slow compared to the Windows driver. But when I played some games in Windows on my notebook(Radeon 9000 Mobility) the last time(1 Year ago, approximately), this was true for DirectX games only. A friend of mine, who has the same hardware, still has problems with OpenGL games like Half-Life 1 and Jedi Academy in WinXP, games that perform really fine with fglrx in Wine.
Implementing a wrapper for windows graphics drivers is surely technically interesting, it's an unnecessary effort, which is better invested elsewhere(For example in making the native Linux drivers better). And it is definitly a thing that ReactOS should have.
Stefan