AGNJ,
If by 'formats' you mean 'drivers' then....maybe. Here is a simplified description:
Mac tries to bundle all the drivers it needs with the install, and so there are typically no drivers available as they come with the OS. For video cameras they don't supply Mac 'drivers' but instead rely on iMovie since all new macs come with iMovie. Apple bundles the drivers with OS X, and in essence that means your camera either works with iMovie or it doesn't. So you have to check the list from Apple.
You would think that you could hook up the camera and copy off the HD video files and then play them in Quicktime. But Quicktime doesn't play many AVCHD formats from the various camera companies (e.g. videos from a Sony camera). (I've found that the free VideoLAN Player does, though). So what most folks do is to use iMovie to import the camera's videos, then use iMovie save as a movie of some kind, encoding into some quicktime friendly format.
On PC the cameras are bundled with some kind of movie editing program that can use the camera's drivers. Hope that helps. Others chime in and correct me