IMDB is not considered a reliable source and should not be used for article references.Wikipedia:MOSFILMS#Critical_reception explictly states Do not include user ratings submitted to websites such as the Internet Movie Database or Rotten Tomatoes, as they are vulnerable to vote stacking and demographic skew.  Also, the film already has multiple reliable sources stating its poor reception, so the IMDB rating detail is not necessary in asserting that stance.

Also see:

Talk:The_Godfather#IMDb_rating
Talk:The_Dark_Knight_(film)/Archive_8#.231_on_IMDb.27s_top_250

For past discussions on removing all IMDB rating references from film articles per WikiProject Films.