I do almost every week. I always check, but if it's a "brown shooter" then I usually skip it (mainly because I think Yahtzee has already said everything he possibly can about them and I find it tiring to here the same things over and over).
I give Yahtzee a ton of credit. I've been watching him for 4 years now (ever since Assassin's Creed) and I've watched the first 100-150 videos probably at least 3-4 times each (I would marathon them when I was bored or depressed, which used to be a lot). When I started watching, I knew almost nothing about any games from 1999 on; now, almost all thanks to him, I've not only played some amazing stuff, but I feel that I understand the thought processes behind the creative decisions that game programmers make a lot more (although I've done a bit more reading and exploration of it by myself, he was the person that encouraged me to do so).
Having said all of that, I have to admit that sometimes I feel that I don't have anything else to get out of him. I continue to watch, and sometimes his jokes or visual gags will surprise me or make me laugh, but I don't know if I have anything else to learn from him. It's still entertaining, and I still look forward to his reactions to certain games (for example, Shadows of the Damned and Catherine, and whatever new installment in the Silent Hill series), but it used to feel like more than just entertainment.