Not all of the announcements at the Sony E3 press conference was unicorns and rainbows (though there were plenty of unicorns and rainbows). The cloud gaming services which were touted as being game-changing (and the only way to play PlayStation 3 games on the PS4), will not be making the system's launch. Instead, they're being pushed back to an ambiguous "2014," meaning it'll miss the system's release.
Gaikai's streaming tech will be hitting the PS3 and PlayStation 4 first, but the Vita services will follow soon after that. Once it does release, it'll use Gaikai technology to provide "amazing gameplay that's fast and responsive," according to Sony, granting instant access to PlayStation 3's biggest hits as well as those hitting the new system.