i researched a few php frameworks (sy2, zend, cake, li3, kohana, etc.) a little while, and by far i'm most satisfied with lithium (li3, http://lithify.me/). depending on 5.3 seems to open up a wide range of possibilities and oftentimes i feel like 'this is the way to do it', whereas i felt like 'the framework is getting in my way' with sy2 for example.