Since when? They are in the trailer.
yeh, for the robots. not for the players.
edit:
why would valve remove classes from gamemodes!?!?!?!??!?!?!?!?!?!?!
I dunno, I read somewhere they were removing those three :u presumably because fire wouldn't do stuff against robots, not sure about headshots/backstabs
eXtine the commentator has tested it and he said all nine classes will feature...?
oh okay I stand corrected