Generally, comedic-based gaming videos. Such as comedic reviews. Sorry, "reviews". But, I also upload funny, highly-edited fail montages with my friends, because they don't take nearly as long to make (Maximum usually 10 hours compared to somewhere between 30-50+) to act as a buffer to give me more time to work on the bigger stuff.
Honestly, I'm still working on my niche, also. I currently mostly only have two series that I do, but I want to branch out of that; I just need to figure out how/what to make outside of that.
Tl;Dr: Combine Egoraptor's Sequelitis, Game Theory, and JonTron. There ya go...