When watching Youtube videos, I like to see a laid back or humorous style of Youtube commentary, rather than one that is dry and boring or overly technical. For an SEO related subject, I like Matt Cutts style. He's very knowledgeable of his subject; at ease in front of the camera and comes across as a regular person. I like the style of some of the gamer personalities who have channels as they have so much energy, it's hard not to watch.
Share your favorite Youtube commentary style to watch or use (when making your own videos).