'Man of Steel': 15 things we learned from the first trailer
The 'S' stands for 'hope'
While in the previous "Superman" movies the "S" was a Kryptonian symbol meaning "The House of El" (i.e. Superman's family name), in the new film it's been changed to mean "hope," as Clark points out to Lois Lane near the end of the trailer. This ties in well with the overriding theme of hope running throughout the new spot - not to mention Jor-El's quote before sending baby Kal-El away from Krypton: "our hopes and dreams travel with you." Of course, to everyone else it'll just mean "Superman."