you might to give applecare a call.
when i got mine, i thought it had a 2mm hairline scratch at the base of the stand. it did not bother me because i was happy with the machine's performance. i still called applecare though to let them know about it.
i spoke to the rep for 2 minutes and then before we hang up, i was asked if there was anything else i need a help with. i told him that i wish i ordered a trackpad instead of a mouse, and i wish that it has a superdrive. next thing i know, the rep said that a trackpad and a superdrive was on its way. i received both items the next day. wow! talk about customer service.
last sunday, as i was cleaning the imac, i realized that it wasn't really a scratch but just a smudge. it came off easily with a damp towel.
end of story. happy camper here