Since the other thread is way too long to sort through, we have a summary document on the Wiki. These names are leading the pack on the Wiki document [in NO particular order]:

Kitsune [Japanese for Fox]
Thunder [Thor]
Viper
Zorro

Please go to http://fox.wikis.com/wc.dll?Wiki~VFP8CodenameSuggestions~VFP to add your comments and vote.