The xf86-input-evdev 2.1 driver has added support for axis inversion, touchscreen support, runtime calibration for absolute devices, axis swapping, mouse wheel emulation, and drag lock. In addition, this driver has runtime configuration property support, but this capability won't yet be in a released version of the X Server until version 1.6.
The release announcement (and source download links) for the evdev 2.1 driver can be read on the X.Org mailing list. In addition, more information about this release can be found on Peter's blog. To build the evdev 2.1 driver X Server 1.5.3 or manually patch this driver due to the EVIOCGRAB change.