According to The New York Times, because of the high return on investment marketers get from their direct mail campaigns, direct marketing won't be going away anytime soon. Instead, more marketers are going green, attempting to be more environmentally friendly with their campaigns.
In addition to using common sense solutions, like using a clean list to avoid sending duplicates, they offer other tips such as using water based ink and recycled materials as well as encouraging recipients to recycle their mail.
Another fact they cite is that every dollar spent on direct mail results in twelve dollars in sales.
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The New York Times.