It has been common for step releases to just happen on a random Tuesday. If there were a new case design or radical change it would have been part of an event.

It has been common for step releases to just happen on a random Tuesday. If there were a new case design or radical change it would have been part of an event. Here's one they did for laptops: http://appleinsider.com/articles/10/04/13/apple_releases_new_macbook_pros_with_intel_core_i7_i5_processors http://appleinsider.com/articles/10/04/13/apple_releases_new... And one for iMacs: http://appleinsider.com/articles/10/07/27/apple_updates_imac_line_with_intel_core_i3_i5_and_i7_processors http://appleinsider.com/articles/10/07/27/apple_updates_imac...