Both renunciation of action and the selfless performance of action lead to the supreme goal.
But the path of action is better than renunciation.

Those who have attained perfect renunciation are free from any sense of duality; they are unaffected by likes and dislikes, Arjuna, and are free from the bondage of self-will.  The immature think that knowledge and action are different, but the wise see them as the same.  The person who is established in one path will attain the rewards of both.  The goal of knowledge and the goal of service are the same; those who fail to see this are blind. 

Perfect renunciation is difficult to attain without performing action.  But the wise, following the path of selfless service, quickly reach Brahman.

As I said in my article yesterday, we have to get past the idea that we can solve all the problems of the world and let God do it working through us.  That's what is means to be "free from the bondage of self-will".
It's fine to renounce worldly ways, but we need to help others find the path as well.  That is the type of "selfless service" this is referring to.  Gaining spiritual knowledge is important, but only if you use it to help yourself and others realize their spiritual potential.