Okay, might as well get this out of the way. For a couple months now I've been telling users not to count on Nvidia's Legacy driver program, that Nvidia would be following AMD's lead and ceasing updates making the drivers compatible with newer versions of X.org. Well, it's now happening.
The 173 branch has been updated to 173.14.75 with a couple bug fixes and support for Xserver 1.8. This branch supports the GeforceFX and some Quadro cards.
The 96 branch has also received a couple bug fixes to bring it up to 96.43.18, but it's Xserver Support stops at Xserver 1.7.
According to Phoronix, there are no plans to update the 71 series legacy driver, and that this release is the end of the road for the 96 legacy driver.
As of right now NVIDIA hasn't updated their even oldest legacy driver (the 71.xx.xx series), but it's doubtful they will especially with their 96.xx.xx driver not even receiving X.Org Server 1.8 support. For those with NVIDIA graphics cards older than the GeForce 5 series, this basically means it's the end of the line for having proprietary NVIDIA driver support on newer Linux distributions.
Presuming Warren goes with Xserver 1.8 for Mepis 9, this will mean support for any Nvidia cards older than GeforceFX will be entirely through either VESA or Nouveau. http://nouveau.freedesktop.org/wiki/