As promised, Sony is still going to deliver a free version of Driveclub to PlayStation Plus subscribers. The version offered will be a stripped down version of the full retail release. It will include a selection of 10 cars, 5 tracks, and 11 variants of those 5 tracks. That's essentially an offering of 11 tracks, all of which will be from one in-game country.

Game director Paul Rustchynsky offers up an explanation of how this isn't merely a demo.
The PlayStation Plus Edition hasn’t changed. It’s hardly a demo because you get access to all of the game’s features online and offline. The difference is that you only have 10 cars and you can only race in one country (which gives you access to 5 tracks with 11 distinct variants).

The PS+ version of Driveclub will release alongside the full retail version on October 8, 2014.