Related to issue #3.

I added support for using properties/getters for label creation when using the ParamConverter from the SensioFrameworkExtraBundle. In your routing file you can define which property or getter method to use.

Use the ParamConverter in your controller to get the entity:

use Sensio\Bundle\FrameworkExtraBundle\Configuration\ParamConverter;

/**
 * @ParamConverter(name="user", class="MyBundle:User")
 */
public function viewAction($user)
{
    //
}

In your routing.yml define which property/getter to use in the breadcrumb labels:

users_view:
    pattern: /users/view/{user}
    defaults:
        _controller: MyBundle:User:view
        parent: "users_index"
        label: "{user}"
        properties:
            user: fullName

This will get the user entity from the request (which Sensio's ParamConverter has converted from an id to an entity). It will check if the entity has a public property fullName. If not, it will try to use the public getter method getFullName(). If that also fails, it will try to use the entity's __toString() magic fuction.