Update: According to both PSU.com and VG247.com, Sony has confirmed that cross-game voice chat is currently not part of PlayStation Plus.
Today a sleuth from TheGamerAccess.com (linked above) has spotted as part of an E3 2010 press release confirmation by Sony that the rumored PS3 Firmware 3.40 update will arrive on June 22, 2010 and likely will include the long-awaited PS3 cross-game voice chat!
To quote from the Press Release: "PlayStation users can purchase PlayStation Plus membership through PlayStation Store on PS3 only.
Users need to install PS3 system software version 3.40, which will be released on June 22nd, to enjoy PlayStation Plus."
Finally, to further substantiate this news, on Sony's official Portugese Web site it states: "Cross-game Voice Chat: invite your friends to chat online no matter what game you're all playing, even if they aren't members of PlayStation Plus."
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