The Steam client for the Public Test Realm will be available for download Wednesday, May 13th.
If you own a Steam copy, the PTR client will be automatically added to your library in Steam, so you can download directly from there.
Also, the PTR server will be coming down at 7am Wednesday for a patch and character reset (wipe).
Patch notes will be posted.
We appreciate your patience while the PTR client moved through the Steam review process.
We are excited to have our Steam players join us on the testing realm!
The PTR FAQ is available here.