Jami, yeah, you got me there. The FoR examples I used were valid only if the solar system consisted solely of Sun, Earth and Moon. In reality, there's other planets whose trajectories wouldn't make any sense at all if the earth was anywhere near the center. But I still think it's wrong to say that the Moon orbits the Earth (and I therefore maintain that the question was stupid). As #25 pointed out, both bodies orbit their common center of mass. If one simplifies these things so much, then people are going to have a problem trying to understand related things. Ever wondered why the tidal cycle on Earth is ~12 hours, not ~24? No way to explain that within the Moon-orbits-Earth model.

"What orbits the earth?" is a pretty stupid question anyway. It all depends on the observer's frame of reference. If the observer is on the earth, then he clearly sees the sun orbiting the earth. If he were on the sun, then he'd see the earth orbiting around the sun. If he were in the vicinity of the SMBH in the center of our galaxy, he'd see the center of mass of the earth-moon system and the sun orbit around their common center of mass (which would lie somewhere inside the sun's atmosphere on the imaginary axis connecting the two), which in turn would orbit the SMBH, etc...