Well, one way or another, 3D will find its way into NetBSD
Tonnerre's project: porting DRI to NetBSD
Discussion about it at the NetBSD tech-kern mailing list
DRI supported hardware status:
And what can be done with NVIDIA hardware:
"UtahGLX also has basic support for nVidia Riva / TNT / GeForce for XFree86 3.3 and 4.0. Someone should port this to DRI."
So if someone ports UtahGLX NVIDIA support to DRI while Michael and Tonnerre port DRI to NetBSD, we're done
But if UtahGLX support gets ported to DRI then all other OSes will benefit, and the new DRI driver will be improved to a point we won't need NVIDIA closed-source drivers anymore. Open-source motivation can make wonders, remember Gnome was born because of the former QT license (QT is the main widget library of KDE, it's GPL now).
If it doesn't get ported, well, DRI found it's way into NetBSD anyway, and NetBSD users will look for ATI instead of NVIDIA
Right now there are NetBSD users who dual-boot into another OS just to get NVIDIA 3D support. If ATI gets supported through DRI I'm sure they'll rather upgrade to ATI than to dual-boot just for 3D.
So, NVIDIA, if you want to release a driver for NetBSD, you better do it now, before an open-source driver appears or NetBSD users start looking for ATI for every platform that supports PCI and AGP.