Did anyone else have Auditorium added to their Steam library for no reason? It doesn't appear to be any type of demo or time-limited version, such as a free weekend. Not everyone got it, but some did. Some have speculated that it has to do with RAGE in some way, possibly Steam messed up the app-ID's or whatever when they were adding the RAGE toolkit and accidentally added Auditorium to RAGE owner's libraries instead of the toolkit.

Yes, I got it too, interesting!

was wondering about that, i received it as well but didn't know whether i had gotten a free copy due to having bought something else like with a valley without wind 2 (got it free since i owned the original)

I made a thread about this on Steam. It is explained there what seems to have caused this:
Suddenly, this game appeared in my Library...

I see nothing new in my library

Do you own RAGE by chance?

nope

Everyone who own RAGE on Steam has now Auditorium in their Library, but not the rest.

Yeah, i see nothing as well.

EDIT: seems rage is required so that explains it!

Meh, never heard of the game anyways. I'm going to be too busy with a certain game coming up soon ;)

+1 to the Rage requirement. I own rage, now i own auditorium.

Do you think they will remove it? i won't really be bummed, doesn't seem like my kind of game.

The problem was indeed RAGE, and it was fixed just now. Auditorium has been removed from the Library.
For more info, check the Steam thread I posted in a previous comment I made.

unfortunately not lol