I've released version 6.70 officially now. This version implements the changes that I mentioned in my last post. So here is the updated FAQ #10 text for IPTC character coding:

IPTC: The value of the IPTC:CodedCharacterSet tag determines how the internal IPTC string values are interpreted. If CodedCharacterSet exists and has a value of "UTF8" (or "ESC % G") then string values are assumed to be stored as UTF-8, otherwise Latin1 (cp1252) coding is assumed. When reading, these strings are translated to UTF-8 by default, or Latin1 with the -L option. When writing, the inverse translation is performed. No translation is done if the internal (IPTC) and external (ExifTool) character sets are the same. Note that ISO 2022 character set shifting is not supported. Instead, a warning is issued and the string is not translated if an ISO 2022 shift code is found. See the IPTC specification for more information about IPTC character coding.

- Phil