It looks like the AirPower charging mat may not be released any time soon.
Apple has reportedly removed nearly all mentions of their wireless charging mat from their website, after no announcement at the recent event.
Searching for AirPower no longer brings up anything and the only place a mention for it can be found is the AirPods page, where it now says 'optional wireless charging case (currently unavailable)'. The case was to be part of the second-generation AirPods, that would have a wireless charging case as part of the update.
It's not clear anymore what's going on with AirPower. It seems earlier this year there were technical issues with overheating and circuits inside the mat. We'll update you if Apple comments on this, but at this point we won't be seeing AirPower for a while (or ever).