One secret is to keep you money in a different exchange. They react slower then MtGox does. I sold all my BTC for 2 dollars more than the asking on MtGox. Also you can see where it's going to bottom out so you can put yourself in a good buy position.
As long as the liquidity is there. Most people flock to MtGox because of the depth. Even though some of the other exchanges have better prices it could take a little longer to find a trade. Nice sell though. Glad it worked out for you.