Well buddy, it is MVC according to the documentation, and the Twitter example itself uses the file AboutController.php. That's reason enough for me to give it that label.

It may not be good mvc, or even a good framework. Of course, whether it's MVC or not has nothing to do with the point I was making: that websites should tell the visitor clearly what the website is about.

If it looks like a duck but wears a shirt that says "goose"...