Going down on a circumcised girl

You're wrong. They sometimes remove the whole clitoris.

Google suggests to me that it's no big deal.. why the heck does it matter? In some ways the vagina looks prettier, not that it was really a very pretty thing to begin with...

What the heck are you on about? If you google 'female circumcision,' the second result down is this page from the bbc website. http://www.bbc.co.uk/health/physical_health/conditions/female_genital_mutilation.shtml

Near the beginning of the article it says:

'There are three main types of circumcision:

The removal of the tip of the clitoris
Total removal of the clitoris and surrounding labia
The removal of the clitoris and labia and the sewing up of the vagina, leaving only a small opening for urine and menstrual blood - a process known as infibulation'

So yeah, it's clearly no biggie...