For those of you who are contemplating acquiring an Apple TV, instead of a Mac Mini, to fulfil their multimedia fantasies for their lounge-room, I would suggest not looking past Plex. I own a Mini and used to use MediaCentral, but when I came across this baby, which is even open-sourced and free, I was blown away by how much better it is than either having an Apple TV or any other solution.
Plex bridges the gap between your Mac and your home theater, doing so with a visually appealing user interface that provides instant access to your media. Plex can play a wide range of video, audio and photo formats as well as online streaming audio and video. The real power of Plex is found in its library features: Organize your media into versatile libraries, automatically retrieve metadata from the Internet, and display your libraries using one of the visually stunning skins.
You are able to get your hands on tons of online video and image sources, through the use of it’s AppStore, which is free.
Once you add your movie or TV show sources, it goes on to popular tv and movie information sites, such as IMBD and gets for you, the theme music, all the season and episode information, so give you such a rich amazing experience.
The interfaces are skinnable, so you can get your hands on tons of other third-party skins, or make your own. Download and try it out, and be sure to read the wiki help notes as it is crucial, for ensuring you name your files correctly: