Glide was open sourced relatively recently. It would take some time for someone to port it to the Nvidia, S3, etc. chipsets. I doubt those other chipset companies are going to take away valuable engineering time and money to support it. Maybe we'll see the Unified drivers improve a bit, but thats probably it.
I also doubt its going to be much of a big deal as time goes on though. OpenGL and DX are going to take over. The open sourcing of Glide was the last nail in its own coffin.
Hopefully UT will be the last built-for-Glide-screw-competition game. And hopefully the OpenGL and DX support will get better.
BP6, C-366/550 (x2 very soon), 320meg
CL TNT2U 180/230
BP6, P3-700@770 (for now), 320mb, eVGA MX Plus (dual CRT), waiting for VIVO module