UPDATE: This just in from Eurogamer Reviews Editor Oli Welsh: The patch was 133MB and downloaded and installed in a couple of minutes. When the game booted, it then recommended a further install from disc which took about five minutes.
It unlocks open and private racing lobbies, community features such a meassage board, mail and gifts, Gran Turismo TV (a store for downloading video content - all free at the moment), the Museum (cards/photos about automotive history that can be traded) and a news service on the title screen.
ORIGINAL STORY: You'll only be able to play Polyphony Digital's PlayStation 3 exclusive racer Gran Turismo 5 online if you download a day one update, Eurogamer can reveal.
Sony's confirmed gamers will need to download the 133MB update before they play the game if they want to take their racing skills online.
The update takes Gran Turismo 5 up to version 1.01, and adds online community features.
Without the update, the game give players an error message when they try to take the sim online.
The update is in addition to GT5's 6.4GB optional hour-long install you can opt for the game to unpack chunks as you play.
Gran Turismo 5 has 1031 cars, which translates to an overwhelming list that we reproduced in full.
Gran Turismo 5 will be released at midnight.