Update only available over KIES
The Epic 4G Touch is getting its Jelly Bean today, courtesy of Sprint. Don't bother looking in system settings for a notification, as this one is only available through Kies due to its large size. Sprint is not listing any specific changes on its update page, but this update to build GB27 should bring with it the usual Jelly Bean goodies like Google Now and Project Butter.
Hit the forums for more discussion about what's new and improved, or for help updating using the Kies method.
Source: Sprint; Thanks to everyone who sent this in!