When it comes to sales, the Mustang is currently kicking in the Camaro's teeth. That doesn't seem to have stopped Ford from continuing to improve the car. While the profile remains the same, every panel on this car, save the roof, has some sort of camouflage. The big changes seem to be happening in the front and rear, but it's difficult to make out any details.
The headlights and taillights are nearly completely covered, but it looks like they retain the current design. This car is wearing Brembo brakes, but it doesn't appear to have particularly aggressive tires or aero, meaning this most likely is an everyday Mustang GT. The rear exhaust does have some emissions equipment attached. This could mean updates to the engine and maybe with a bit more power. We're already expecting the rumored 10-speed automatic that's being developed with GM.
The car in the photos doesn't appear to be a special edition, but the camo over the rear side glass has us pining for an Bullitt edition. Really though, we just want the green paint. Expect to see the refreshed Mustang alongside one of the new special editions in the next few months.