Professional video editing on Mac I'm totally unaware about Macs and video editing. I have an iMac and a Sony camera that produces .mt2s files. I've heard that the Mac is the best for graphic and video editing, so I was wondering how should I work with this file format on a Mac?
Sony codes their recording in their own format, hence the .mt2s, and they want you to use a Sony Laptop to edit the footage. Anyways, there is a Mac app called, MPEG Stream Clip, that converts the footage to any format you want at any frames/second you want. You can download it for free from Squared 5, http://www.squared5.com/svideo/mpeg-streamclip-mac.html. 

It is a great piece of free software.

As for video editing software you can use Apple's iMoive (for the amateur) or purchase Apple's Final Cut Pro (wait until July, they are releasing a new version).