Polyphony Digital's Christmas gift to Gran Turismo 5 Prologue players (the game is out in Japan, in case you weren't aware) arrived around noon on Christmas Day in the form of an update enabling online play.
What's that? You thought Prologue was supposed to be online from the start?
While the game was originally announced that way, just prior to its Japanese release earlier this month, Sony announced that online play wouldn't make it into the initial build. Instead, it would be enabled as part of a Christmas update.