As it did with Resistance 3, Sony plans to impose its “PSN Pass” on Uncharted 3, meaning multiplayer access to that game will be subject to a one-use code included with all retail copies. That’s per Juan Jimenéz, Sony’s software manager for Spain.
https://lastchance.cc/sony-confirms-psn-pass-program-required-for-resistance-5818629%3C/a%3E%3C/p%3E
Online pass schemes, earlier implemented by Electronic Arts, THQ and others, are an indirect way for a publisher to get a cut of used sales, but they’re more intended to incentivize buying new.
Interview with Juan Jimenez, Software Manager of Sony Spain [The Vault (Spanish) via Joystiq.]