I've had several questions in the last few weeks about the setup I use for recording videos. I did a lot of research before I started publishing videos on youtube and here is what I settled one.

Camera

When shooting demonstration videos (reloading, gunsmithing, etc) I almost always use a DSLR camera. I only use Canon (I will explain the reason why later) and I own several of the DSLR bodies. I have (2) each of the T2i and 7D for a total of 4 DSLR bodies. There isn't a huge difference between the two models when it comes to video. I use the 7Ds because they have a higher burst rate when taking photos. The 7D also has weather sealing so I can use them in the rain or leave them in the garage overnight without worrying about moisture affecting them. The 7D also allows me to film for longer durations without the sensor "overheating." Neither of these DSLRs have auto-focus continuously applied during video recording. That really sucks if you are trying to record motion and distance; IE- me running through a shooting course.

Audio

For videos shot outdoors or where I am constantly moving around I use a Canon Vixia HF G10. This is a traditional "camcorder" that does not have the picture quality of the DSLRs. It is still 1080 HD but significant less megapixels. You cannot change out the lenses like a DLSR but it does look great outdoors nonetheless. I can record for much longer durations on this camera which is great for working outdoors when I am trying to catch something on camera that is difficult or takes multiple tries.
Audio is one of the most overlooked aspects of video production on youtube. There are a lot of channels out there using a decent camera, but then rely on the on-camera mic. The on-camera mic is usually meant to sync audio from a dedicated audio source. I record most of my videos with a Zoom H4N
and Azden SGM-1X
shotgun mic -OR- a Sennheiser EW G3
wireless lavalier mic.
In my video editing software (Sony Vegas Pro 12
) I take the external recording from the Zoom device and sync up the audio captured from the camera mic. Then I mute the camera mic in and use only the external audio. This makes an ASTONISHING difference. All of the shooting I do at indoor ranges uses the external mic source because the camera mic pics up all the room noise which sounds awful. It also doesn't do well recording very loud noises like gun fire.

Why Canon?

When I first started with DLSRs, Canon was blowing away Nikon in terms of video. I think Canon still has the edge (thanks to Magic Lantern) but Nikon has significantly improved their video. Magic Lantern is an open-source software that is NOT produced by Canon, but by Canon enthusiasts. It provides a level of granular controls that simply aren't found on consumer grade or even the cheaper professional cameras.
I spent a SIGNIFICANT amount of time and money to get the point I felt was acceptable. In the future I will shoot some videos that show the difference between the audio and other things such as lighting or camera lenses.