hershie.... good article.
We had quite a long discussion going on here about just that some time ago. Check it out, there are some very interesting observations:
http://www.xnations.com/showthread.php?s=&threadid=1221
I personally think that most (60% or more) of the agencies out there that mass mail will not be doing it for very much longer. You have to do it 110%
clean now. No more BS such as fake "opt out here" links that don't work.