-OLEDs currently don't have the same level of brightness and lifespan as LED LCD displays (
here).
-SSDs are currently around 9-10x more expensive per GB than HDDs. They will become stock items when the price drops.
-Apple will use Intels latest chipsets when they become available.
-Apple are already using the most current battery technology economically feasible. To use any more advanced battery technology would greatly increase the cost of the computer.
-What case design changes do you think are necessary? Apple kept the aluminium design from 2003-2008, so i wouldn't be surprised to see the current Unibody design stay until around 2013.