Supposedly it will happen, but nobody knows exactly when or for who Danica will be driving in NASCAR.
First of all, I want to say that there is no reason why Danica shouldn't have a great career in NASCAR. She's obviously a talented driver, and she can learn how to drive cars fast with fenders on the car.
But I will say that I don't expect Danica to win 9 championships in a row in NASCAR, because that seems to be what a lot of the "Taxi cab" snobs think will happen. You know who I'm talking about. There are elite open wheel fans who sneer down their noses at anything NASCAR, and refer to our sport as "Boys driving taxi cabs in circles.", since the sentiment is that it takes no real talent to drive in NASCAR.
Ask Juan Pablo Montoya how hard it is. Ask Scott Speed. Ask anyone named Fittipaldi or Papis. Ask former open wheel star Tony Stewart how hard it is to win in NASCAR.
Tony is probably the only former open wheel guy to make it really big in NASCAR's ranks.
Can Danica do it in NASCAR? Of course she can. She probably will too, but don't expect spectacular results too soon. Driving in circles with fenders on one's car can take time to procure as a talent.
Good for Danica. Come racing where it's as real as it ever gets.