Marketers are making enormous progress in improving the effectiveness of email, but expensive technology is becoming increasingly important in reaching an email audiences. The good news is that new email techniques are pretty transparent, at least many of them are, so by watching how the leaders are using email (i.e., receiving and reading their email), we can copy their breakthroughs.

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  IBM has discovered that "click-through" surge when links to further information are presented in graphic, rather than text, links.
• Cisco has decided to encourage audiences to read further into each email they receive by increasing the use of graphics toward the end of the email, pulling the eye down.
• Overall, companies are sending less and less email that’s unexpected or unrequested.

WSJ.com: Marketers Give Email Another Look, 2006-Jul-17, by Suzanne Vranica

OgilvyOne says heatmapping tests show particular words in an email draw
more attention from recipients. People in the small-business sector
tend to gravitate to messages that talk about "service" or "solutions,"
says Jeanniey Mullen, OgilvyOne’s senior director of email marketing.
Another finding: The word "free" doesn’t spark much attention.