Well, loud music and noise in general can temporarily damage your ears. The more you do that (when your ears feel "full", I don't remember the actual term) it builds up and eventually leads to permanent hearing loss.
You know how when you're in your car you keep turning up the music to compensate, especially if you get on the freeway or drive with windows down? Your ears get used to the sound and you turn it up more to hear it better. A lot of people do this with earbuds.
Now, when you ride with earbuds in and have music playing, the tendency is to turn it up. You'll really have to resist that urge and instead turn it down.
Besides the aspect of overexposure to loud music, most earbuds aren't designed to block out the noise that earplugs would, so you should find some that do or you'll not be doing yourself a favor later on from the damage wind noise gives you.