With regards to transitioning WordPress towards an application framework, what do you, wp devs and enthusiasts, think about moving WordPress on top of an established PHP framework?

I know it's come up from time to time, but usually it's for the wrong reasons and at inopportune times. In fact it's entirely possible, as evidenced by Drupal 8, which is migrating a lot of its inner workings over to the Symfony framework:
http://symfony.com/blog/symfony2-meets-drupal-8

Some of this technical stuff is beyond me, but the gist of it is as simple as it is beautiful: Less reinventing of the wheel, more common ground and healthy separation of tasks.

My vote goes to Laravel, purely based on hype and no facts.