Hi Tomahawk!
Thanks very much for reporting this! It looks like it's related to one of your USB peripherals -- perhaps your Fitbit Base Station or the PNY Technologies USB 2.0 FD -- that we're not handling correctly.
Could you try again with one or both of those peripherals disconnected from your Mac? I'm not sure which (if any) of the other USB hub devices listed in the crash report are built-in to your iMac... If it still fails and you have other USB devices attached, try disconnecting them too.
I'll file a bug report so that we can take care of this ASAP.
Thanks again!
--
Darius