Okay, so it might be just a mock-up but if so, why bother listing any prices?
VG24/7 spotted a telling image in the history section of Gaikai's website . As you can see, it may give us a clue as to the cost of renting PS3 games on the PS4.
As you can see, Uncharted 3: Drake's Deception has a $5 rental price tag, and Far Cry 3 can be played for $6. If accurate, a standard five-dollar rental charge may be quite attractive for those who missed some great last-gen games. Gaikai is the cloud service Sony purchased back in 2012 for $380 million, and it will power PlayStation Now, the Netflix-like subscription service coming to Sony's new console. However, that image doesn't give us any idea how long we can have the rental for.
We won't have much longer to wait, though, as PlayStation Now should roll out in North America this summer for the PS4 and PS3. The Vita, smartphones, tablets and Bravia TVs will also support the new service.