ok how come the 13" MBP has a solid back plate with screws covering the upgrade material . And the 13" unibody macbook non pro has the nice button release tab that uncovers the upgrade material making upgrades a snap no screws . I guess the question is how come the pro has screws and the non pro has an easy tab release? I hate screws they don't want to unscrew easily and get lost. And how come the MBP's battery (7 hour battery) won't replace the aluminum's macbooks battery? thanks in advance and new to Mac so excuse the long sentence's