On the surface most of the popular PHP frameworks are not much different from each other. Basic MVC separation, some sort of dependency injection container (actually a service locator), Composer and standardized autoloading, etc. Once you dig into the coding aesthetics then the differences start to become clear. Yii isn't PSR compliant, both FuelPHP and Laravel make liberal use of Facades and/or __callStatic to preserve the style of static function calls that are prevalent in CodeIgniter. I guess what makes Laravel stand out is the sheer amount of documentation and examples that are available, both on the website and in the code itself. This makes it really easy to get started.

Me, I'm not really keen on the Component::function() syntax. Feels like a crutch to me. Especially when people go out of their way to avoid specifying namespaces by abusing class_alias. Plus you're not really saving that many keystrokes compared to, say, $this->app['component']->function(). (Yes, I like Silex).