What you see in this video is a midship Ferrari in Camouflage driving around Fiorano. While it could be another test session for the LaFerrari, the camouflage and the turbo sound bring a few questions. Why does it sound different? What is this car?
I think there are 3 possibilities:
a) Ferrari is testing a new FXX Style super track car. The old one was based on the Enzo, so with the new hypercar as a base it would be time for a replacement.
b) Ferrari is doing R&D work on a Turbo/Hybrid street car. There are videos of Californias testing with obvious turbo sound as well.
c) Ferrari dropped in the new V6 Turbo for F1 to get some track time. Motorsport-total.com requested info on it and Ferrari didn't give a clear answer, just like Renault didn't. They are rumoured to have done the same in a WSbR 3.5 Chassis. Only Mercedes ruled out any pre 2014 testing.
Interestingly Maranello has done the exact same thing a while back when F1 switched from V10 to V8. They equipped a Enzo with the engine and ran tests. Now that Ferrari is said to be behind in development and that the new Ferrari V6 is the thirstiest of them all it seems that they play every trick to get in front and stop Red Bulls dominance.