Next release for Jaunty?

Ubuntu is not a "rolling" release distro, and so does not follow all the available update(s) for program's and drivers. But when there are security issue's involved, Ubuntu is very fast in updating drivers and sofware with security issue's. One of the fastest imo.
Mostly X updates comes with kernel updates, and brand new versions of Ubuntu.

So how would I get a newer version of this driver besides updating to the Karmic development release?

X Updates: https://edge.launchpad.net/~ubuntu-x-swat/+archive/x-updates/
Updated versions of X.org drivers, libraries, etc. for Ubuntu. This PPA is for stable upstream releases of X.org components.

 If you're looking for something even more bleeding-edge, please see the xorg-edgers PPA.
https://launchpad.net/~xorg-edgers#ppas

For example, for adding stable X updates:
1) Open a terminal (Applications->Accessories->Terminal)
2) Enter the following command:

gksudo gedit /etc/apt/sources.list

3) Add the following two lines to the bottom of the file:

deb http://ppa.launchpad.net/ubuntu-x-swat/x-updates/ubuntu jaunty main
deb-src http://ppa.launchpad.net/ubuntu-x-swat/x-updates/ubuntu jaunty main

4) Save and close the file.
5) Enter the following command at the command prompt:

sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys
3B22AB97AF1CDFA9

6) Enter the following commands at the command prompt (each on their own
line):

sudo apt-get update
sudo apt-get upgrade

Thanks for that info :) Thats kind of what I was after.

But doesn't it make sense that if a new driver with bug fixes and performance enhancements over its predecessor is available that it go to the mainstream users via a regular repo update?

When you have problems/issue's with your graf. driver I would recommend this PPA to event. solve problems. And there are known issue's with intel drivers on Jaunty. Otherwise I would not recommend to enable this "source".