I'll agree, but being knowledgeble of film history, does not make a great critic.
The best film critics thouroughly understand film. Roger Ebert excels in this, which is why his opinions are so valued.
There is a difference between the film critic who thinks The Hot Chick is "hillarious fun" and the film critic who heckles the bad movie within the review. Read Ebert's reviews for North, The Hot Chick, and The Time Machine sometime. They're literally humor essays.
