Just a heads up for those of you who considered purchasing an LG WCP-700 charging mat, it does not work with the Lumia 920. I left my Lumia on it for 15 minutes, and although the mat beeped acknowledgement and showed that it was "charging" the phone never entered the charging state.
Looking on the QI wireless standards page (Products - Wireless Power Consortium) the WCP-700 is not listed as QI compliant -- a similar product, the WCD-800, is listed there but I don't have one of those so I can't test it.
Looking on the QI wireless standards page (Products - Wireless Power Consortium) the WCP-700 is not listed as QI compliant -- a similar product, the WCD-800, is listed there but I don't have one of those so I can't test it.