I just have to second that you likely won't be ripped off by a taxi, just be smart about it. Take only yellow cabs, not "gypsy cabs" and lincolns that honk their horn at you incessently while you are trying to hail a real cab. Cabs have improved dramatically from the past, practically (they all must accept credit cards) and in theory (cabbies are not allowed to talk on their phone... but often will :-p).