It's been a while since the last OpenChrome driver release for VIA hardware (14 months), but in order to offer compatibility with X.Org 7.5
/ X Server 1.7
, the team quickly rushed out a new release.
Some of the improvements made to this VIA DDX driver that competes with xf86-video-via and xf86-video-unichrome include VX800 support, basic VX855 support, CX700/VX800 integrated TMDS support, ARGB cursor support, and oanel mode-setting code rework. There's also been assorted bug-fixes and other work piling up in this driver over the past year too.
The release announcement for the xf86-video-openchrome 0.2.904 driver can be found on the X.Org mailing list