If you are in a client facing role, they are likely to care. I am not talking about working in HMV, but if you are a lawyer, accountant, banker etc then it would not be a good thing!
Of course if you're in a role like that, but surely that's obvious enough.
I'm the manager of a retail store with what I'd call a fairly professional image (much less casual on the whole than some other, similar stores). I have one full sleeve of tattoos, and the other arm has work on it. I wear short sleeves. My ears, although theres nothing in (or between, hohoho) them now, are fairly obviously scarred from when I had scaffolds and tunnels and so on in them.
But I have short cropped hair, I'm tidy, I'm presentable, and I present a friendly and affable front to the public, so there's no problem.
I'm not saying NO employers discriminate, but there are plenty that don't.
Yes if you want to be a city type maybe you should be careful, but there are many many jobs you can do even if you're inked up or you've got a thingy in your ear or whatever, provided the art you have about your person is either coverable, or at least inoffensive. The firm I work for now, I offered to cover the tattoos up, my line manager had a look at it, and said no don't worry. If he'd wanted them covered, I would have.
I know I'm 'only' in retail, but it's fairly high end as retail goes, and I consider myself presentable. What I'm driving at I suppose is that having tattoos or piercings does not make you unemployable in the way it once did, at all. If you keep it sensible (no hands, neck, face tattoos, and be willing to remove any piercings if necessary) then honestly, you won't find yourself out of a job.