I guess all tutorials are user generated, but Tildee offers a site to house all that content. Simple enough concept-you have something you know how to do, you put it here and allow others to search for it. Plus it has a ranking so you can rate the various tutorials you look at.
The only major downfall I see so far is lack of content. Yes, you can find lots of content, things like Photoshop, Audacity, and other tech-related things. A variety of non-tech as well. But still not enough. When searching for Android, I only found the one to the left, and one on a specific Android app. So lots of work to add more content, but hopefully by seeing reviews of it everywhere, more people will add to it. A pretty good concept.