So here is the official language from NERF:
"NERF N-STRIKE MEGA THUNDERBOW Toy
(Ages 8 years & up/Approx. Retail Price: $39.99/Available: Fall 14)
Awesome NERF MEGA performance transitions from blaster to bow with the addition of the N-STRIKE MEGA THUNDERBOW toy. The bow’s dynamic arms and traditional pull back system can fire five NERF MEGA whistler darts in a row up to an amazing 100 feet. Includes 10 MEGA Whistler darts and holds up to five NERF MEGA darts at a time. Available at most major retailers nationwide and HasbroToyshop.com"
NERF confirms to us that the Thunderbow will be ready for a Fall 2014 release. I'm not sure how excited I am about a $40 price tag. I was ready to spend it on the Rapidstrike, but I was really glad when the price went down more. Seems a little steep for a foam-firing bow system. Who am I kidding, I'd spend it!