AND the wing is gone, replaced by a larger spoiler than what was man-dated last time they carried one.

What Stewart & Vickers said about testing it:

It (the spoiler) was on a bunch. It didn't seem to be a big balance change which was good," Stewart said. "That means you won't have to invent the wheel necessarily. It was a balance shift, but it wasn't a big balance shift. You've got two kinds of grip you've got aero grip and you've got mechanical grip. The spoiler is the aero grip and the tires are mechanical. The mechanical grip is real important because it doesn't know if you are running first in line or 10th in line. I'm more of a mechanical guy."
"I thought it (spoiler) was good," Vickers said. "I thought it added a little bit of front downforce, which is a good thing. I think it's going to be more accepted to the fans. It looks cooler a little more retro back to the older car. We haven't been in a lot of traffic yet, so the big question is how it's going to handle in traffic. Theoretically, from what I've been told, the difference between the two is that the spoiler is better in traffic. The spoiler is going to be more efficient in dirty air and a wing will be more efficient in clean air. Once you get in a lot of turbulence, the spoiler's not going to lose a lot of efficiency while a wing really will."