Peter Hutterer on Wednesday officially released xf86-input-evdev 2.7.0 as the latest evdev driver release. Smooth scrolling for X.Org came around this past summer and was then pushed into X Input 2.1, which then made it into X.Org Server 1.12 along with the further X Input 2.2 update. The Synaptics driver quickly took advantage of smooth scrolling and now there's the evdev support too in a released/stable version.
The other noteworthy item for xf86-input-evdev 2.7.0 is then, of course, multi-touch with X Input 2.2 when using supported multi-touch hardware. Using multi-touch with this generic input X.Org driver additionally requires mtdev. The mtdev library is the Multi-touch Protocol Translation Library, which translates the kernel input event stream into a simplified form that's more friendly for applications. The mtdev library can also handle finger tracking and some other capabilities.
The release announcement for xf86-input-evdev 2.7.0 with a list of changes since the earlier 2.6 release can be found on the X.Org mailing list.