Gaming and commenting channel. Cynical, british to the bone, intelligent and entertaining TB, along with his crew do all sorts of gaming videos. Starcraft 2, WoW (cancelled), WTF is? (first impressions - mostly indie games) and co-ops with other gamers - Terraria with Jesse Cox, Magicka with Yogscast.
Another gaming channel. Humorous and again british Simon and Lewis are well know from their's Minecraft series - Shadow of Israphel and other. They also make some other stuff with Hannah helping them out. For example - Simon plays The Witcher 2 and many many more.
Crazy Russians and their supercars. Cool videos of drag races, drifting on the roads of Moscow and other russian citys. Great montage and festival of horsepower.
4. Gradual Report
One crazy bastard. Australian/Serbian/American (?) Danny makes videos of everything. It doesnt matter if the topic is: "Milking Cows" or "How to piss" it still will be funny. Be prepared for major brainfuck and absurd. Check his serbian lessons.
5. Day 9
Starcraft 2 enthusiast, ex-pro player, and one of the best known commentator of Starcraft. Cool guy.
Most of the people know him already. Makes nice news-style overviews of viral videos. His humor gets tiring after a while and recently is out of ides, but still, he is great.
7. Ice Flows Studios
Makes great, useful photoshop tutorials. His radio voice and talent helps you understand this dreadful programme.
8. Zeitgeist Review
Normal american guy doing game reviews. What's unique about it, he never gives a score, just tells you if he liked the game.
9. The Gamestation
Huge gaming channel, featuring many well know youtube personas (TotalBiscuit, Yogscast, Husky). Plus it has a weekly (?) news channel with Layne Pavoggi.
10. Zero Punctuation (not a youtube channel)
"Zero Punctuation is The Escapist's groundbreaking video review series starring Ben "Yahtzee" Croshaw. Every Wednesday Zero Punctuation picks apart the games so you don't have to. Called "hilariously cutting ... first legitimate breakout hit from the gaming community in recent memory" by Boing Boing, see why gamers love it and developers fear it." - prepare for really fast talking.