I get around

As I continue my countdown to Cancun, and how I plan to venture past the safe harbor of the resort, my main concern is "how do we get around"? I've been lucky to live in an accessible city like Philadelphia; we have 2 main train lines, a myriad of buses that criss-cross the city, and regional lines that can connect you to Delaware and central Jersey. Something tells me that Cancun's system won't be as sophisticated.

In college I took a trip to Puerto Rico and had the same concern. However, my friend and I were able to conquer the bus system there, and I was able to [barely] communicate with my broken Spanish and some of the local's broken English. I hope that Cancun's system will be as easy to figure out because taking cabs everywhere will surely take away from my "shot" money.