Yeah it gets a bit technical in the Wiki.
Content does "just appear" but it's new content. So think of it as a way to not have to navigate to a site to read it's articles or browse articles. Helps for blogs and news sources. I have Polygon, AndroidPolice, Lifehacker, TechCrunch, and Verge all in my pocket or browser without navigating to them.
I'm glad I stayed with the X1 - it's what I know. For all those getting the PS4 - that's cool, enjoy. The Xbox support isn't perfect, but I think, at the moment anyways, its better than the PS4. I just wish good gaming for everyone. The only thing that disappoints me is that I'll never be able to play with OT members on the PS4 .