angular2.min.js - 568K
Version 1.4.*
angular.min.js - 148K
File size really increased (Angular1 * 4 == Angular2), if compared with first version. Something went wrong.
Angular 1 is a fully fledged framework, you can use it on it's own, but 2 seems to depend on rxjs, and it's also bigger.
To me that seems like a step backwards.