I'm thinking about getting a new MBP for grad school, with the intent of putting my old iBook G4 into reserve and giving my iMac 20" to a family member who is in dire need of a new computer. But I'm not sure what this upgrade is going to offer in terms of computing power. What can I expect for the Nehalem system architecture and Mac OS 10.6, and will they be released by August 09?