CodeIgniter is still PHP4-friendly. It's not "hot" by any means. CakePHP is still actively developed, but it's pretty miserable. (It's slow, too - so much so that framework devs usually benchmark against it because it's so reliably slower-than-everyone-else.)

If you're going to use PHP, I can't really think of a good reason to use anything other than Symfony2.

They're removing PHP4 compatibility in 2.0, which is being more than actively developed. And it at least gets as much traffic as Symfony does: http://www.google.com/trends?q=symfony%2Ccakephp

As far as not using Symfony 2, I wouldn't use anything not marked as stable in production. That goes for CakePHP as well.

I just built an app on both codeigniter and cake... and I prefer cake by far. Cake gets in your way a little bit, but it's good for me since I wouldn't describe myself as a "classically trained coder".

CodeIgniter has a big following, but so does Symfony2 and Kohana.

CakePHP is what we swear by at work. Still works for us, and we can't wait for 2.0.

we use it all the time too, but i get questions asking why not codeigniter...