$49.99 to upgrade to all game content, but there's a catch
Ahead of Driveclub's October 7 launch on PlayStation 4, here's a video breaking down the game's normal, full-price version on PSN and Blu-ray compared to the free-with-a-membership PS Plus Edition. The latter offering comes with access to every game mode, 11 tracks, 10 cars, and a single location, India. More than just a beefy demo, then.
If PS Plus Edition players decide to upgrade to the full-fledged Driveclub -- 55 tracks, 50 cars, all 50 tour events -- that's going to cost $49.99, a slight discount versus buying the full game outright. However, this access to new content is only good "as long as your PlayStation Plus subscription remains active," apparently. Which isn't going to be worth the discount for some of us.
If that's indeed the case, it'll be better to figure out if you enjoy Driveclub for free and then buy the game separately, not upgrade with strings attached.
DRIVECLUB PlayStation Plus Edition Details [PlayStation Blog]