Canonical developer Timo Aaltonen has announced X.Org Server 1.19.2 is now available via x-staging along with the driver rebuilds. X.Org Server 1.19.2 will be coming to Ubuntu 17.04 and it should officially land in the archive next week. This is a big update in comparison to X.Org Server 1.18.4 currently found in Zesty.
Mesa 17.0.1 is also going to be landing as another big update over Mesa 13.0 currently found in Ubuntu 17.04.
Details via this blog post.