The Cobra's price will be $40-$42k depending on options. Best bet on a demand based markup when they first drop.
Ford wasn't crazy enough to go after the ZO6 with a Mustang. That would take such a godawful amount of power to make up for the design disadvantage it would be hard to make streetable.
The Cobra will no doubt be competing with the 2006 GTO Judge (480hp). Now that will be some fun.