Regarding the Silithids

[Tulune]

Have they still reverted back to normal Silithids as beta pets?

[Qraljar]

Quite frankly, I have to confirm that as of current, they are back to their old models, who knows. There is a good chance Blizz is just rescaling the pet size and it will be back next build or the build thereafter. And yes, I am an optimist xD

[Kalliope]

This thread is what you're looking for.

Soriid and Haarka are back to their old forms.

The brainbugs have their own names and are untameable.

[Darknez]

The "old form" Silithid rares are also untameable on beta.
I couldn't find Clutchmother Zavas to test her current tameability state.

Silithid Ravager rare is gone and has been replaced with a whole bunch of Silithid Ravagers in the same area that are colour changers (red, blue/green and tan only - no yellow it seems).

I do have the original Silithid Ravager and he appears to remain Tan only (judging by the stable master view). The new ones appear blue/green in the stable master view.