Tried it. Only things under the in development header are PTR classic and live.
If I go into the wow program file on the hard drive I can navigate to the beta directory and launch the 9.0 version of the wow client, but when I log in, it shows the realms in red, and says incompatible and promptly disconnects.
Do you use the beta version of the launcher? We had someone see the same thing but could only see the SL Beta option when they swapped it back to the normal version of the Bnet launcher.