Whatever you agreed with his reviews or thought he was a fool, Roger Ebert is as mainstream of a critical presence as you can get, and he and Gene Siskel were quite a team on their weekly-syndicated SISKEL & EBERT AT THE MOVIES.
Richard Roeper took over after Siskel died, but he lacks the magic and fun that the Siskel/Ebert regime displayed, for that both men worked for rival papers in Chicago, and didn't care for each other in real life...which added fuel to the fire when they absolutely disagreed in regards to a new film.
Anyway, they've dug out the old VHS tapes (of which they could find) of both men's reviews from the 1970s into recent-years with Roeper, and put them up on the internet for everyone to watch.
Click and see Ebert be a bonehead when he trashed DIE HARD. Watch Siskel be one of the few critics back in the day give a negative review to SILENCE OF THE LAMBS, and watch Roeper......be a schmuck.
http://bventertainment.go.com/tv/buenavista/ebertandroeper/