Regardless of what other people do in this kind of situations, the best thing in my opinion would be to sell because more people might join out of ignorance while looking to make quick profit and the price may indeed increase for a while but will eventually crash.
Interesting you would mention that. I was reading about the momentum trades where people buy ONLY on the price move, which is counterproductive in my opinion. The "Value vs. Momentum" is decreasing. No change in inherent value (or perceived, actually) but an increase in momentum. That's my signal.