TV shows like LA Ink are glamorizing tattoos and you may see candidates who are covered with "art" from head to toe. Their body tapestry, as it is often called, is sometimes more important to the candidate than paying the bills.
Employers are allowed to create a policy regarding the display of piercings and tattoos while at work. Is it yes to two ear piercings but no to lip or nose piercings? Yes to forearm tattoos and eyebrow piercings, but no to neck tattoos? It is up to you to decide what your policy should look like.
Where physical labor is required, employers such as repair shops and manufacturers should have a policy that limits all body jewelry to minimize the possibility of workplace injury.
Other employers may find the display of body jewelry and tattoos by employees to be draw to their clientele, but even these businesses should have limits in place to avoid employees overdoing it.