I've added pubsub-create to the response as the XEP-0060 states:

If no error occurs, the pubsub service SHOULD create the node, generate a NodeID that is unique within the context of that service, and inform the user of success (including the NodeID in the response).

and then:

Note: When a service successfully creates a node on behalf of the requesting entity, it MUST return an IQ result (in accordance with XMPP Core). If the node creation request did not specify a NodeID and the service supports creation of instant nodes, the service MUST specify the created NodeID in the IQ result. Similarly, if the node creation request specified a NodeID but the service modified the NodeID before creating the node, the service MUST also specify the modified node in the IQ result. In all other cases, the service MAY specify the NodeID in the IQ result but the node creator MUST NOT depend on receiving it from the service (since the node creator can determine which node was created by tracking the 'id' attribute that it specified for the IQ-set).

so while previous response was valid according to the XEP, I do think that having pubsub-create in the response with node can be useful.

@bmalkow Do you agree? or should I rollback this change?