In my last post I wrote about Movie Vault, so I'm going to loosely stay with the subject and suggest that you take a look at the recently updated Leonard Maltin Movie Guide. We looked at the original version many months ago, and I think the app is better now.
For US $2.99, you get the complete set of Maltin reviews, and since the app is Internet connected, you get new reviews as they appear.
Here are the things I like: The app is quite fast, and when you start typing a title or a name, it auto-completes. There are trailers for newer films out there. Names of actors and directors become hotlinks that you can click on and perform a search on those names. There is very nice integration to Netflix. You can put a movie in your instant or DVD queue, or you can even move that film to the top of the list. There are also rental links to iTunes, and you can share reviews from this app via email. The app has welcome links to IMDB (for really in-depth info) and Amazon (if you want to purchase a film on disk).