I said it briefly at $532/BTC today. It just dropped down to $520. if you had a large investment (~50 Bitcoins), so that makes a big difference in a few thousand dollars...
Should i keep it for a little longer and hope it jumps again?
Or sell now as it seems to have already peaked?
I would keep them for just a couple more days lets see if the price could actually reach $600 if that happens then you could sell. Do not wait to long before the price starts going to down again.