There are so many PHP Frameworks out there. I've used CakePHP and am using CodeIgniter. There are several other ones out there Symphony, Yii, Kohana and many many many more. I'm having a hard time deciding if I want to learn another php framework.
I really like CodeIgniter. I love the light weight footprint, but it's missing a few things that I get sick of writing. Namely CRUD features for admin panels. I don't mind writing the code just if you have a lot then it gets tiresome coding those by hand. I found GroceryCRUD which is nice, but it has it's own templates, and I'm not sure I can integrate it into ones I'm looking into.
CodeIgniter also lacks an authentication system. There are many written, but I think I'm going to stick with writing one from scratch. While the code will typically the be same, I can at least customize it to my own needs as necessary.
Another plus to CodeIgniter and very few other PHP Frameworks is that the command line is not important. While this isn't an issue for work related items as I have command line control, my own servers do not, so it makes it difficult to cross things in my learning process.
So I'm thinking of learning some other design framework - HTML5, CSS3 frameworks. I've actually been playing with HTML5 boilerplate and integrating it in to a template system.
There is another platform I'm thinking I might look into making apps with - Pokki. It's like Adobe Air. I never quite got Adobe Air. I'm hoping Pokki will allow me to do things that I couldn't figure out with Adobe Air. It'll be interesting.