It's supposed to make other..."activities" more exciting.
I don't know about the possible pleasurableness of it, but I have a friend who hurt her tongue on her boyfriend's tongue piercing, and I've heard all kinds of stories about tongue piercings getting stuck in braces or in the gap of someone's teeth while kissing (not sure how much of those are true, but you never know), so I think you would have to be careful with it.
I thought it was for oral?
Didn't know that. Never kissed anyone with a pierced tongue.
thought it was for giving head to a guy to make it more pleasureable
Kissing is not any more exciting until you bite it on accident and cuss like a sailor! Lol but oral sex is a little better (for the ladies, I doubt it makes a big difference for guys) you can even get tongue rings that vibrate, thats fun!
..... Not really kissing....