Save up your money and buy it with cash. I saved for two months and today I received my 15" uMBP!!!! Knowing I own it free and clear of any credit payments is a much more satisfying feeling. Its like paying cash for a vehicle, you appreciate just a tiny bit more.
Get it on credit, put the money away. Pay off the card, get credit. Sounds dumb till you want to buy a house and all the loan companies tell you to go F ur self.