Up for Debate: The replacement refs

There's been some growing chatter in the world of NFL fans about the replacement referees [1] and the job they are, or aren't, doing. How do you feel about the job the replacements have done? Have you seen blatant instances of either loss of control of the game or worse-than-normal blown calls? Do you worry that the NFL isn't too concerned about bringing back the regulars because the league knows the viewers are still going to watch either way?