Easy to learn, has very clean and short syntax, lightweight, not bloated, flexible and easy to extend.
its has many extensions. but the documentation complicated so newbiees stay away. till you learn php well
nice framework well featured cli model generations a big plus
worked with this excellent. documentation awesome
ZF. Best design and fully supported by pro developers.
Codeigniter best framework, before I was trying cakePHP but it was too tricky to develop with..
Very very fast