Unless there was a Internet disruption and/or power failure at the exact instant the firmware was downloaded and installed, I would say the odds of the unit being bricked are highly unlikely. Unfortunately, there's no way to tell until you have access to the camera (catch-22).
Again, if the camera was connected to your router via a wireless connection, there's a strong likelihood that it simply was unable to reconnect after the reboot. There's a good chance that simply rebooting the router or the camera will fix the issue. There are MANY other ways to restore connectivity as well, including performing a factory reset and reconfiguring the camera.