I've become a recent fan of Marques Brownlee for his tech reviews. He was purported about a year ago to pull $700/day on YouTube. This is in addition to other streams of income he has from the various projects he's involved with. He's 25 years old now and started doing tech reviews when he was 13. Not only is he knowledgeable, but has a nice, pleasant, easy-going manner and not at all pretentious and gimmicky.
I even like the way he says his cliche tagline.
Peace.