I believe the newer ones (2012) are much harder to get into. While the older models used magnets to hold the screen in place, the newer ones use adhesive. You

I believe the newer ones (2012) are much harder to get into. While the older models used magnets to hold the screen in place, the newer ones use adhesive. You now need guitar picks and a heat gun to get into it. See ifixit for details: http://www.ifixit.com/Teardown/iMac+Intel+21.5-Inch+EMC+2544+Teardown/11936/1 http://www.ifixit.com/Teardown/iMac+Intel+21.5-Inch+EMC+2544...