WordPress MU

Other than to avoid naming collisions with other plugins, is there any other benefit to using a class structure for plugins as opposed to just referencing plugin-specific functions directly?

e.g.
$class_instance = new class1;
$class_instance->function1();

class class1 {
function function1 {
add_action('some_hook', array(&$this, 'function2'));
}
function function2 {
// do something
}
}