I was about to but then I got to the end of your post. I like IMDB because it's made me discover a tonne of movies that 20 years ago, would just not be possible; especially the information about silent films. It really is an amazing tool, but the other side of the user input isn't as great and the Top 250 list is obviously based on popularity which negates it. Still, I must admit when I first got into movies in the early 2000s (when GBU was probably about #20) I used the 250 as a guide to watch the "best movies ever made"; AND The Shawshank Redemption is a great movie, but I was a fan before it was cool to like it I really think that a major problem now is that a lot of movies in the past 10 years or so that are being produced in Hollywood aren't that great, but I have an idea that the studios somehow manipulate the IMDB voting system so most blockbusters appear on the list during the first couple of weeks of release.
I gave up when The Lego Movie made the top 250