But one of the greatest benefits of using these services over your own in-house e-mail program is that you are able to follow your readers. The tracking reports show you specifically who (the actual e-mail address) opened the e-mail, which e-mail bounced (bad address), who forwarded the e-mail (although you won't get to see to whom the e-mail was forwarded -- that technology does not exist yet), and if you provided links to information on your Web site or other Web links, you will see who clicked on those links. In addition to tracking the recipients of your e-newsletter, using an e-mail marketing service will give you piece of mind that your e-communication complies with antispam laws.
I realize that these technologies are well established; but I think this is an intrusive approach to marketing. It is perilously close to spying on newsletter subscribers. Of course this sort of feedback is extremely useful, but it is not worth the risk to the breakdown in trust, especially with a law firm. Just because a thing can be done, does not mean it should be done.