spcomputing: So the "A new network interface has been detect" box did not come up after plugging in the Uno?
You will have to bear with me until a real Mac user comes by ;)
No, no dialog box appears when I plug in the Uno.
spcomputing: Does "Network Preferences" show the Uno anywhere? If the driver enumerates the Atmega8/16u2 it should show up as a device on the network. If so, what kind of properties does it have?
Network Preferences shows a USB Modem, Not Configured. I do not believe that this is the Uno, however, because the entry persists even without the Uno plugged in.
I am fairly sure the Arduino application detects the Uno board, because when I plug the Uno board in, there are two more selections to choose from under Tools > Serial Port.
Thanks for the replies!