Local community structure is fine, but the participation with experts on global level is something new to most of us.
I would add my understanding of expert's subjects, please correct me if I miss some point:
Client - aimed on performance/bugs/improvement of existing and suggestions of future functionality of Waze app. Including beta testing and close interaction with devs.
IOS/android - aimed on platform specific client's behavior, basically its interractions with system and other apps.
Editing - aimed on map editing in actual WME, setting rules and defining good practice for editors, cooperating on WME scripts creation and testing, then advertising them to editors community... and making suggestions to devs regarding WME performance & functionality.
Beta editor - aimed on close cooperation with both - devs and Editing experts - in order to get new functions developed correctly and ensuring new WME release with good performance and minimum of bugs.
Navigation - aimed on tuning routing rules together with requirements for map data. TTS, voice guidance, etc.
Points - aimed on point awarding system and ranks - to get system "cheatproof", justified and clearly communicated to users. Also answering points related questions from users.
Social media - FB & G+ local fan pages and similar stuff
Localisation - aimed on consistency of translation strings and coordination of transiflex projects. Also new TTS languages.
Hope I got it right.
if it looks strange, it's my phone's fault
Editing & Client Expert, AM @ South-West Slovakia
Waze 18.104.22.1682 on HTC One, Android 4.2.2 @ white Škoda Octavia