In a PlayStation.com Forums thread about the existing Uncharted 2 chat system, a Naughty Dog staffer with the handle "ReklissAbandon" reportedly said that "the next PS3 firmware update is going to allow cross game chat."
Currently, that alleged confirmation is "deleted" (presumably by ReklissAbandon), but the text reappears as a quote a couple of posts down the thread. We've got the full quote after the break in case all record of the statement should meet with an unfortunate accident, and we've also reached out to Sony for comment. In the meantime, please temper your excitement over hearing your friends' voices with a bit of healthy skepticism.
[Thanks to everyone who sent this in!]