Melody in Intrumental Music

I remember friends in college comparing Mozart and Beethoven. At this point in my life, 9 years later, I don't think there is a comparison! Both are just so distinct and well regarded that it wouldn't feel right to put them on a teeter-totter.

According to one friend, Mozart had the melody, and Beethoven had the chords. Um, What about the 5th symphony? What about "Ode to Joy?" I think both of them had it. Anyhow, I wonder how those guys approached writing melody. Mozart seemed to just bubble to the top with melody. His work is populated with them. However, he didn't really challenge the harmonic status-quo until much later in his life, towards the end actually. It seemed that Beethoven challenged the norms of harmonic structure his entire life. This doesn't mean he just ignored melody though. How can a person not get "Ode to Joy" totally stuck in their head?

With luck I won't make a value judgment, but I think there is something to creating melodies that are hummable. Don't get me wrong. Any melody that comes from the heart (cheesy but true) is a good melody. But the hummable ones? Maybe that's what get's me.

Hey look at that- I just compared Beethoven and Mozart. Oops.