My top 3 are:
1. Game Sack: No Explanation Needed
2. Turbo Views: No Explanation Needed
3. Video Masters TV: I have been a fan of this show for a few years. They cover a wide variety of games for for all systems, both new and old, as well as PC games. In addition, they also talk about obscure B movies, comics and action figures.
A show I used to watch was Retroware TV. Their production value is really high as their video quality is top notch. They cover a wide variety of consoles as well. Their videos actually inspired me to check out the Turbografx when I saw their review for Ninja Spirit. You can tell the hosts are passionate about the games they review, but sometimes they don't get some of their facts straight.