The generally agreed upon best method for video editing with open source software on the Linux operating system involves two unique programs.
Kino
The Kino video editor project, like most open source programs, is currently and always under development. The stated goal of the project is to be a viable choice for all video editing purposes, which includes being simple, reliable, and able to import/export in a variety of useful formats. While Kino could very well be what you are looking for in a free video editor for Linux, the general consensus is that Kino should be used in conjunction with another program called Cinelerra in order to achieve the best results.
Kino has full support for Firewire (IEEE 1394) DV capture and for recording back to the camera. This makes it the preferred method for "grabbing" video off of the camera and saving it to your computer to be edited. From there, though, most enthusiasts and professionals then abandon Kino in favor of Cinelerra for the actual editing process.
Cinelerra
Cinelerra is considered the most advanced open source program for video editing, fully featured for layered framerate - and resolution - independant video editing, as well as creative effects. It has been likened to a combination of Adobe Premiere Pro and Adobe After Effects, only open source and built for the Linux operating system. Cinelerra is sold as part of a software bundle from Linux Media Arts but is also available in a compilable "Community Version" (Cinelerra-CV) which is free of cost.