That's interesting. I haven't personally seen a dance, but that doesn't mean it isn't happening.
All of my top keywords are still going strong. My particular hit seems to have been in the longtail.
Do you happen to have ads above the fold? I put a couple up in the middle of last week, just to get an idea of what I could make vs other monetization forms. It's probably a coincidence that my traffic is down some now, but it's worth asking.