It looks like this baby or at least while Hayley is preganant can create hybrids. But, it appeared Tyler took the blood straight from the baby to create a new hybrid (then drank from Hayely to finish the process).
The big question is the part about the sire bond. Is it a bond to Hayley? To the baby (so while Hayley is preganant she is the "sub" for the baby)? Is it a bond to both of them? Or is it something we haven't seen before, a sire-bond that is linked to whoever you drink from to complete the hybrid creation process?
It's a little stupid that Elijah didn't immediatily realize that the baby's blood , if it can create hybrids, it should also cure Klaus's venom. I imagine they'll realize that as Elijah goes into hallucinations (though with the information dump she gave Elijah JUST before Klaus bit him, hell I'm not sure why Klaus didn't realize it--or he did, why didn't they both immediatly realize this...
Along with what the witch's have said, it'll be interesting to see from what direction the true threat...with hybrids...actually comes from. I see three possibilities (though four could happen, but it seems doubtful). Either Klaus starts an army. Hayley decides to become a true queen and makes one (possibly to protect herself from all the wackjobs coming after her). Or, I think the most likely, a third party who I think is the werewolves (possibly her clan).
As others have mentioned, it will be interesting to see at any point if Hayley gets killed, will she become an immediate hybrid? What would it do to the baby?