It is my guess (and it is just that) that the AGPgart drivers will be available roughly at the same time as the nForce3 Pro chipset, which as I understand it is single cpu chipset for the AMD Opteron that has an AGP slot and is aimed at the workstation market. Since Windows doesn't yet have a 64-bit operating system that will fly on an Opteron, Linux is the only 64-bit game in town. Thus in order for nVidia to be able to sell this chipset to motherboard manufacturers, there will most likely have to be AGPgart support by that time.
Asus P5e | Core 2 Quad Q9450 @ 3.4GHz | 4GB G.Skill DDR2 @ 1020MHz | X-Fi XtremeMusic
EVGA GTX 280 | PCP&C Silencer 750 | Dell 2407WFP | Windows Vista x64 | Rocketfish full tower