Kids-In-Mind.com
Kids-in-Mind doesn't do age-specific rating like that G, PG, PG-13 and R rating done by the Motion Picture Association of America. Instead they assign 1-10 ratings for three distinct categories:
1) Sex & Nudity
2) Violence & Gore
3) Profanity
So a film with a 1-8-5 rating will have minimal sexual content, but lots of violence and quite a bit of profanity. A great site for parents looking to get the lowdown on the movies their kids want to see.
Plugged In
This Focus on the Family site’s strength is in the sheer amount of valuable, detailed information it packs into film, DVD and even CD and video game reviews. Its weakness? While reviews are written from a generally conservative Christian perspective some films (Hellboy, Dark Knight, etc.) are treated far too charitably – having a self-sacrificing hero, or “Christ figure” in a film doesn’t mean the film has anything to offer Christians.
Movieology describes itself as "your ticket to engaging the spectacular world of film from a bedrock of biblical truth." These guys are Reformed, amusing and they will make you think. The site is now longer being updated, but the reviews they have there, and more importantly the presentations they include on how to think about films are well worth checking out.