Blizzard has launched the Public Test Realms (PTR) once more to test patch 2.2.3—so head to your Account on the official website to download the new client. Make sure to delete your old WowTest Folder (2.2.2).
Hortus: The 2.2.3 PTR is up and available to players.
As a reminder there are no pre-mades for 2.2.3.
Tigerclaw: Some bugs have varying impact. There are performance related issues in 2.2.0 that are adversely impacting people on lower end single processor systems, and there are a lot of those people playing the game. We’ve made a decision to address those issues as quickly as possible.
The latest PTR patch notes can always be found at http://www.worldofwarcraft.com/patchnotes/test-realm-patchnotes.html