ORIGINAL: forpaws
And to add, body language also. If their bristles were up and not friendly barking, they don't like each other. But sounds like they want to be friends to me.
Yes! and if you sense it is friendly I would defintly set up a play time as much as possible becuase eventually their frusteration of not getting to meet or play could turn into aggression. Its always best to let your dog play with the neighbors if they get along. BUT dont rush your dog into their yard or visa versa, that could casue territorial issues. Have them meet on leash out on the street and then proceed to one of the yards if things look ok. Usually if they enter together and all toys are picked up it will be a great and easy introduction!