When do you think the first games that will take advantage of 8x will be out?
Probably about a year after AGP dies
AGP 8X has numerous issues currently in terms of developers trying to use it(when I say use it I mean for something besides a SYA texture backup). You need to have a system with either dual channel high speed DDR or RDRAM in order to provide enough data for the rest of the system and the AGP bus at the same time. Currently you are likely to find the amount of rigs that match that criteria to be quite a bit lower then those of us with high end video cards(P4 systems with PC133...).
Utilizing AGP8X will be titles that are pushing vertex data through the roof or those that start utilizing 3D textures etc, things that we aren't close to seeing. Now, with all of that said, AGP8X can provide you with a performance boost today under certain, and rather rare, circumstances. That may end up being an extra 5FPS for half a second once a week though, so it isn't really worth it for a gaming rig if it is going to cost you extra. If it is no extra cost, then absolutely go with AGP8X.
BTW- AGP8X is worth it if you are using it for a MCAD/Viz setup with a decent board. It is not a useless technology. What will likely end up happening is that all of us enthusiasts will be running SPCI boards for some time when AGP 8X starts to be exploited by games. It will certainly be useful at some point, but not in the reasonable lifetime of a board for those of us who post here
