I tried 'Withnail and I'. It then brought up a new screen with 'movies most like' (with generally accurate results) and 'movies least like'. There's a link to 'Tell me more about this movie' which pulls a summary from Amazon. Trailers and previews come from IMDb, as do external reviews/critics. User reviews are also pulled from Amazon.
There's a 'Movie in a nutshell' tag cloud as well.
Finally there is a 'what are you in the mood to watch' option, which is a 3 word 'nanogenre' - for Withnail there were six options, such as 'funny friendship weird' and 'england subtlety emotional'. Clicking on any of those provides a selected list of other films that match the chosen criteria.
Nice resource, with the additional bonus of creating you own 'Mymovies' option to keep tabs on your favourites. If you're into films, this would be a great one for you!