Well... the big players in the 9xxx series have been released. The 9800 GTX is the most powerful single GPU atm and the 9800 GX2 is a nice bundle of joy, but I am planning on keeping my 8800GTX until Nehalem comes out. I was planning on doing a massive upgrade all at once (i.e. motherboard, triple channel ram, processor, and vid card) a few months after all the new architectures are released.

So here is my question: I doubt it will be a year before another technology / gpu series is released... anyone know what it will be? I've heard some things here and there about G94 chips, but does anyone have the low-down on the next generation of video cards (if there is one within the next year)?

Well, there's whispers of ATI bringing their next card to market early.  Unfortunately until ATI's next gen comes out NVidia will be resting on supplying any new cards to the market, which is the downside to NVidia's lead in performance (marginal performance lead, but still enough that they aren't pushing to get their next gen cards out).  I honestly don't think we will see new cards until Q4 this year as they refine manufacturing processes on the smaller die sizes, and increase the yield per wafer.

9800GTX is the fastest single-GPU solution at the moment true, but that's only because the 8800 Ultra has been discontinued.  The Ultra beats it in enough things for it to still hold onto the crown, imo.

The GT200, which is speculated to be the 9900 line, is rumoured for Q3 of this year.  I wouldn't expect it before September, and maybe delayed until later, but that's just my personal speculation.  The 9900GTX is hoped to be single-GPU and as fast as the 9800GX2, and the 9900GX2 is expected to be the new top performer.

R700 could come at any time.  Most expect before the GT200s, but who honestly knows.  Ati says 2008, that's all we really know.  Speculation is multiple cores on the mid and high end models.  Performance is unknown, but rumours are saying closer to a 50% increase rather than a 100% increase which some generations have had.