My main guideline on strike selection is to stay close to the money, and shoot for a delta over .45 or so.
I also try to take into consideration the trading costs, since I use ETRADE which is pricy. I also choose my option date based on the number of daytrades I have left. I just had Etrade remove margin, so I will be able to trade more freely after sometime tomorrow.
I am still flabbergasted that PCLN rose that big today. I've never seen such a huge rise before. IT will definitely be on my watchlist from now on.