Like Sony, Canon defaults the video quality to the second-worst option, 7 megabits per second at not-full-HD 1,440x1,080-pixel resolution. That means the video you get out of the box looks more like the bottom, artifact-ridden grab than the top. This might make sense if it was a cheap model with videos destined for nothing more than quick-and-dirty Web upload, but not in a $1,000+ model. There's no reason not to default to the second-best, 17Mbps full HD mode, which looks quite good and likely won't have the playback issues you might run into with the best-quality 24Mbps model.
(Unfortunately, I was unable to get sufficiently comparable grabs for each mode. Nevertheless, I thought they were close enough and worth the illustration.)