I have 3036 miles on my 2005 Suzuki S83 Boulevard and the pipes are bluing. This is an untouched bike straight from the dealer with nothing more than the check-ups at the dealership. Suzuki won't do anything about it. They tell me it's a "cosmetic problem" not a "performance problem". Then they passed me off to the Extended Warrantee folks. I'm still waiting on their decision as to what they will do. Here is a picture of what one of my pipes looks like.

http://home.woh.rr.com/marlinman/blued1.jpg