Thanks for the tip. I got in touch with the Wireless Power Consortium and they quickly gave a pretty clear reply.
My question was "I saw that LG's Nexus 4 phone had recently been registered as a low power receiver. The registration specified HW Rev 12. Do you know if earlier HW Revs are not compatible? Or whether the HW has changed to add Qi compatibility in Rev 12. I have a Rev 10 Nexus 4, and found that it does not work with the certified Nokia DT 900 transmitter. Rather than charge, it constantly cycles on and off connecting and disconnecting."
And their reply is "You have correctly noticed that the Google Nexus 4 was recently added to the on-line database that identifies all Qi compatible products. Although the earlier Google Nexus 4 model is not in that database, the earlier model (the one you own) does work correctly with all Qi wireless chargers except the Nokia DT 900. The revision of the Nexus 4 that is now certified will work correctly with the Nokia DT 900."
So if you want a Nexus that works with the Nokia charger, you need Rev 12.