On their twitter account (a href="http://twitter.com/phpmagnet">phpmagnet) PHP Magazine have been conducting a survey of PHP frameworks and their popularity through out the community. They've gathered these statistics together into one trending page.
The data below is generated automatically from twitter. To cast your voice you can simply send a reply to @phpmagnet with frameworks you use, like, or suggest.
As it stands at the time of this post, Drupal seems to be at the top of the "interest" charts with CakePHP coming in second and Symfony in third. Zend Framework tops all three lists (Suggest/Like/Use) in popularity. You can read more about the project here.