Amy,
Thanks for the alert - I'll pass this on to the ArcGIS Online team. As you'll know the labels are all autogenerated based on the underlying vector data, which may be sourced from one or more companies, so if we are able to request corrections it might take a little time to filter through the system back into our service.
Can you tell me exactly which basemap / ArcGIS Online service you are using? (the Basemap is listed in the Contents window).
Regards
Mike