I feel the same about piercings as I do about tats: I'm all for 'em, as long as they're applied judiciously. Obviously, piercings are generally less permanent; you can take 'em out if you want to, and they're barely noticeable (except the stretched ears, which just make me wince). Most people don't realise I have a pierced ear unless I decided to put a ring in it.
Tattoos are trickier, and I tend to think you should generally get them if they mean something to you. Those things are permanent, so you don't want to take them lightly.