Specifically, the alleged laptop's battery would be non-removable, very slim (consider the MacBook Air's battery) and able to run "...much longer" than the current model. The announcement of a new 17 inch MacBook Pro wouldn't be a very big surprise, but a non-removable battery would. People like removable batteries for obvious reasons.
Mike Rose guessed that we'd see a new 17 inch laptop when we all listed our predictions. We'll all see what happens in just a couple of days.
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