I've been doing monthly emails for about a year. I would say it is AS important and effective as a web site.. maybe even more so. It gets people to come BACK to your site.
I include only information... no 'sales' pitches, except for featuring a couple of listings. I only put in 'teasers' to articles that are on the website... which gets people BACK to the site. The response is tremendous, and the most hits on the website are on the first day of each month when the newsletter goes out.
The issue is that you need to utilize a company that can 1) easily send bulk emails 2) a company that can allow you to put together html email AND which will convert to text email if someone cannot receive html email... 3) an automatic opt-out option (as well as opt in) so maintenance is done automatically, and not by hand, which is time consuming.
The company I've been using is
Constant Contact A sample of my monthly email newsletter (it's just a graphic though... links don't work).
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