Infinite scroll pagination with a Wookmark layout
The code looks pretty good, but here are a couple suggestions:


The semicolon at the top is unnecessary: ;(function(myApp,$){
You use _this in many places where this would work:

Consider Function.bind (see MDN, only works on modern browsers)
This very much depends on personal style

This is a little confusing. I don't write jQuery much, but it isn't clear what the first this is referring to (and the second this has a different meaning than the one above, which is also confusing):

$.fn.wookmark_pagination = function(options) {
  return this.each(function() {
    new WookmarkPagination(this, options).init();
  });
};