Oh there are plenty of other celebrities to watch, but there wouldn't be enough "drama" and a evil vs good feel to the show with out the horrible "O".
This show needs the drama to bring people back. I think they are fortunate that the writer's strike cleared the way for people to watch. I know I would have had other programs to watch in lieu of this one, if the strike had ended.
Apprentice viewership was way down the last time out. Now that the holidays are over and the regular season has pretty much ended due to the strike, this show should see a big ratings hike. People are going to tune in, just to see O get the boot... but not too soon