Update: since this one has written this, at least eight weeks ago, he has not gotten a single credit card junk mail. Guess it just took them a while to get it all out of their system. Hopefully it stays this way.
ma’habocath has tried calling that “opt-out” number three separate times. The junk mail still comes. Doing that probably is just telling them I’m reading their junk and thus encouraging them to send more. (Warning: this link is very NSFW [cursing, nudity] but it is well worth the read, this one promises his good friend.) So, don’t waste your time.