In response to the question posted by the thread starter, it depends on the tattoo and the gender of the person.
Women: I hate big colourful tattoos. I hate pathetic floral or fairy tattoos. Some areas I think are no go like the ***. It is soo 1980s b-list model... or Melanie Griffith. Either way is bad. Good areas are the back, neck, arms and ankle/feet. Odd areas are cool too like behind the ear or near the underarm. Has anyone seen New York artist Rachel Feinstein's tattoo? Is is an image of ants crawling out of a vagina and is near her underarm. It rocks
Icons: Angelina Jolie. All her tattoos are very her. The scripts clearly are important to her and they all are beautiful in terms of where she has placed them on her body. The huge ones on her back echo her curves and the black ones on her fragile arms look like beautiful cuts.
Men: Should never have little cutesy designs no matter how ironic. Also I still don't like messy looking things. An example is Mark Philippoussis' tattoo which was a gorgeous plate of Alexander the Great on his shoulder. He ruined it by adding all these messy flames around it. Eugh.
Icons -Brandon Boyd, Heath Ledger. Both have tattoos they designed themselves. Brandon's are amazing and I love the colour of his koi fish one. See this link:
http://www.geocities.com/incu3602/tattoosbrandon.html
Other rules I think people should stick to when considering tattoos:
1) NEVER pick out of a book EVER! Design your own.
2) Is there any reason for having a hula girl or a tribal elephant on your body? Probably not. A tattoo should mean something to you and that comes before aesthetics.
3) Tattoos should either be black, white or a nude colouring. I think people should avoid the muticoloured sleeves that bikers wear... unless they are bikers of course.
As for me, I am getting my first two tattoos in a couple of weeks. They are both lettering and are both very discreet.