There are many ways a tattoo can look. Personally, I am really intrigued by the style of tattoos that Yann David from Paris does. It's very graphic, but with a little bit of child-like naivity to it. He's not the kind of tattoo artist you'd go to to get the portrait of an indian hammered into your skin - I suppose he needs quite a bit of artistic freedom to invent something on your skin. Expressionistic art? Graphic design? Playful? Abstract? Naive? Neo-romantic? It's all that, and a bit more. It's definitely something different than most types of tattoos, that's for sure.
On his website www.yourmeatismine.com, you can see a ton of examples of his work.