you can most certainly develop it the more time you put into developing your ear the better it will become
a good way is transcribing
start with really easy songs and work your way up!
AND STICK AT IT!!!

cool right now I copy w/e my unknown friend records on the piano at school, but what I really want to transcribe is AsianJoe's c.a.t.s (normal version) and the stop motion version. Right now I can pick up single notes working on 2+ keys at once really hard