It shows S&M is a number one song because of hype, not quality. Also, I'm pretty sure it won't keep the first spot for another week, which just confirms my theory.
I'm here for longevity, when you have a song leading the pack for several weeks it shows how successful the given song is. Otherwise, it's all based on hype.
Either way, S&M is (probably) going down as a number one hit, and that's what matters for some of us. So with that said...
CONGRATS!