I, for one, am not a particular big fan of attempting to "hide" email addresses from spammers, people should just use a proper anti-spam solution (spamassasin, dspam, tmda, etc) instead of attempting to hide their email address from spammers, the effectiveness of this method is questionable, and it makes it difficult to contact people ... Basically is doesn't really solve anything, it's just a poor attempt at fixing a symptom.
This being said, I also realize that many people don't share this view and do want to hide their email address, so publishing other people's email addresses without their content is of course not acceptable.
One non-intrusive way to make an address unharvestable would using writing it in HTML character entities, research done in 2003 shows this works
http://www.cdt.org/speech/spam/030319spamreport.shtml
In any case, I would not be in favor of using automatic intrusive address munging ...