> As long as GT doesn't change the allowable email addresses, you're safe.
You are not safe. Google is regulary adding new domains to Google Talk as part of the "Gmail for Domains" beta test. See https://www.google.com/hosted/Home for more info. > apart from GT not advertizing its extension in disco, Google's private blocking extension is not advertised because Google does not encourage the use of the extension. Google does not encourage the use of the blocking extension because it overlaps with RFC 3921. > we should make simple iq-based protocol for blocking and going > invisible, as a server-side profile of privacy lists. + 1