You can probably wait to buy in for quite a while.
As long as Bitcoin remains as speculative as it is at the moment, the price will remain fluctuating but on a downward trend.
Google trends estimated that btc was worth about $35 without the speculative bullshit that's feeding all of our wildest hopes and desires to sell off our 1.02 btc for thousands. I'm thinking we're going to keep heading for that bullseye until another PR stunt is pulled off and people get a renewed interest that spikes us back to those triple digits.
That is assuming that btc on a whole remains for the most part a commodity and not an actual currency.
but if ebay, paypal, and dwolla take their prodigal son back than that later assumption goes in the trash and then step 4 people...PROFITTTTT