Actually, several threads with people who picked up 17" models today confirmed that the drives are connected to SATA 6 Gbps with a negotiated speed of 3 Gbps. This means the computer has SATA III, but the drive is only SATA II.
I highly doubt that since initial cougar point chipsets had faulty SATA II ports. Apple wouldn't (hopefully) use known bad ports on these MBPs, and the fact that the MBP's were released today means Apple is likely using the flawed chipsets in them.