If you go to the shops today and pick up a PS3, it will cost you around $699. For your money, you get a 40GB hard drive and a SIXAXIS controller.
But if you wait until August 28, for the same amount of money, you'll get an 80GB and a superior Dualshock 3 controller.
It's not rocket science people. It's simple value for money. Don't let your lust for gaming get in the way of a good buy - it's just not worth it.