Hey folks :)
The new identifier datatype is getting ready. Once we have it we will put identifiers into a separate section on items. This is part of our effort to make items easier to scan in order to find the information you're looking for. Right now identifier properties are of datatype string. Please have a look and see if any properties we should migrate are missing or if any we want to migrate should not be migrated. You can find a list at https://www.wikidata.org/wiki/User:Addshore/Identifiers. This list was made by Adam based on statements on the properties. (For the technically inclined: The datatype will change for these properties but the value type will stay string.)
Cheers Lydia