AFrameJS is an MVC application development library, not a DOM manipulation library! AFrameJS leaves the DOM manipulation to jQuery, MooTools, or Prototype, instead providing the parts necessary to create MVC applications.
MVC is a programming paradigm that has been common in other languages for many years. In MVC, Models represent data and its operations. Views are the presentation of the data contained in a model. Controllers are the glue that bind the two together. MVC separates these three concepts, there is no mixing as is commonly found in web apps today. The benefits of MVC are numerous, but the main goal is to reduce the mental load for the developer. Modules focus on one goal at a time. This allows for smaller modules, easier testing, a higher chance of code re-use.
As web development matures, MVC based applications are becoming increasingly common. AFrameJS is being developed to fill the need of having a true MVC framework to develop applications with. Backbone and Knockout-JS are two similar libraries that address this need, now AFrameJS does too.