On his blog, mustapha has posted his Top 10 list for his opinions on PHP frameworks.

Development of PHP scripts without a preconceived plan to manage them is asking for a headache. The goal of a framework is to make the process of writing web-based applications simpler.

An application designed around MVC is easier to manage because it is split into tiers, which allow for independent development. This promotes code reusability by building models, which are reusable throughout the application.

His list includes frameworks like Phrame, Symfony, and CakePHP ranked according to his personal tastes. He does provide some backing behind his top three choices, however - giving his reason(s) for picking them.