As a web dev company we use Yii, as well as Zend and Symphony. Yii was selected to be the primary solution for custom projects in our company, because it's flexible, fast, easy to use and modern. Here is an article explaining what are the major advantages of Yii: zfort.com/...
Take a look at this infographic which introduces the analysis of top 5 PHP frameworks based on Google trends and developers’ opinion: zfort.com/...