Sony finally explained why there is no cross-game chat on the PS3. Shuhei Yoshida, president of Sony Worldwide Sudios said to Eurogamer during an interview that:

“Once a game gets RAM we never give it back,”

“It’s not possible to retrofit something like that after the fact. The game has to use its own memory to do [in-game voice chat].

“There’s always voice chat in the game. But it’s a part of a game feature. It’s not a part of an OS feature. That’s the reason in terms of the ability to have voice chat across different games.”

This is why PS Vita will have chat features, since it carries 512MB rams. PS3 only carries 256 Ram.

So it doesn’t matter how big the machine is, but what is inside that counts!