The laptop will see the introduction of the "Mac Retina Display," which is said to have a very high resolution. ABC News has similarly heard from its own sources that both the next MacBook Pro and the iMac would be getting very, very high resolution displays. Apple refreshed its new iPad with a Retina Display in March.
It's thought that Apple might update the MacBook Pro around WWDC 2012; however, no date was given for the iMac refresh.