It's a backdoor. The original paper describing the hole is (hopefully) entitled "On the Possibility of a Back Door in the NIST SP800-90 Dual Ec Prng"[0]. It's no longer a "possibility".
Uh, yes it is still a "possibility". Unless you have a source I missed, which is possible but please actually cite it, all we learned about Dual_EC from the NSA leak was that the algorithm was designed at NSA. Lots of crypto is designed at NSA; it isn't all presumed to backdoored.