Will the new canonical tag help with issues where you by accident you have indexed by IP address rather than hostname? One has to double check it, but this kind of thing is, one would like to be able to do. One would like to put hostname rather than your IP address. Actually, Google has to consider this concern about the IP address different than the hostname. It will not be bad to go ahead and have that. This is the sort of thing where one does not wish to show up the IP address. Rather than, one wishes to have their host, their domain name. Actually it would be a nice thing to do. But, it is not sure that Google would support for IP addresses yet.