Gran Turismo 4 Online Edition is due out in Q2 2006 and will include six-player online play along with worldwide server rankings and replay upload options.
That's been leaked to us as part of a bundle of marketing documentation, which Sony has yet to comment on.
GT4 Online Edition will include 700 real cars (from classic to ultra-modern supercars), 50 real tracks, and split-screen options in addition to six-player online racing.
There'll also be voice communication support to chat with other drivers and customisable online competitions.
The docs also point to what's described as a huge single-player challenge, despite the game's obvious multiplayer leanings, with B-Spec and Photo modes making it over intact from GT4.
We'd expect to hear more about GT4 Online Edition in the very near future.