Developers mailing list
The probably best place to send your ideas and questions to is the ID3v2 mailing list. You're welcome to discuss every ascpect of the ID3v2 tagging system here.
ID3v2 has its own mailing list, <id3v2 AT SPAMFREE id3 DOT org>, intended primarly for software developers and developers of this and similar standards. You must be a subscriber in order to send a message to the list.
To subscribe, send a blank email message to <id3v2-subscribe AT SPAMFREE id3 DOT org> and you will receive a confirmation email in return. Confirm the subscription and you're ready to go.
To unsubscribe, send a blank email message to <id3v2-unsubscribe AT SPAMFREE id3 DOT org>.
A digest is available on GMANE
There are 230 subscribers as of 12/16/06.