Looking for a Camcorder that Will Work with iMac

I'm in the market for an HD camcorder and before I go out and purchase one I want to make sure I understand how it will work with my Mac (2Ghz Intel Core 2 Duo with 2GB Ram).

I'm currently looking at one of three models:
Panasonic HDC-H520
Sony HDR-XR200V
Canon Vixia HG20

I assume they'll all get along fine with iMovie etc but I'm wondering if there might be pros and cons to a specific model/manufacturer? I just don't want to get stuck with an odd proprietary format that needs to be converted all the time.

Overall, is the process of importing a video and editing pretty straightforward? Are there any things I should watch for in general?