Based on my prior experience (see above) I'll predict the following:
Recall? Forget it. And rightfully so. Unless the discoloration causes people to have seizures, it will not affect the function of the machine.
More likely, for the short term, Apple will continue the current party line of "this is the first we've heard," "bring it to your local store," "you can send it in, but we won't guarantee anything," etc. If you have Apple Care and call the service line, be polite, and patient. The experience will vary widely depending on you, your attitude, and that of whomever you conect to. Some of the people (at least a couple of years ago) were very helpful and seemed genuinely concerned. Others clearly could have cared less... Some customers kept logs of whom they talked to at Apple, and when.
Eventually, Apple will likely agree that the problem is real, is not the customers' fault, and while cosmetic is also an unreasonable thing to have happen with normal use. At least, that is what they did w/ the TiBook. Don't expect the change in attitude to happen overnight. And if you don't have AppleCare and the computer is out of warranty, you are likely going to need to spring for replacement parts yourself. That being said, the process was as painless and professional as could be asked: they send you a box, you put your computer in and send it back (Apple paid postage) and you get your computer back in 7-10 days, sometimes less.
So, in answer to your question, if you don't have Apple Care, you need to figure out how much this discoloration issue would likely bother you. If not much, take your chances. If it will bug you, and you don't want to shell out the money to get it fixed, then I'd return the computer, and wait for the debugged Macbook version 2.0 (sound advice for most products, anyway).
As for some of the more zany suggestions on this forum, I have to laugh. Look, I love my Mac. It could turn bright orange and deep purple, and I'd still gladly use it before I'd touch a crappy Dell Windoze clunker. But dipping your computer in bleach? Repainting it after a month of use? Needing to buy a cover to protect your computer from your hand grease? Maybe you are washing your hands
too much? That's my personnal fav; "From now on, make sure your hands aren't too clean before you compute." Seriously, this sounds like a design/manufacturing flaw, plain and simple, and any reasonable person would hold the manufacturer responsible for making it right.