Litmus released an email analytics service last month (may 2010).
See here: http://litmusapp.com/email-analytics
They boast a very cool "read rate" tracking: they can track normal reads, Skims, and Glanced/Deleted.
How can they track skims and glanced/deleted? This to me seems impossible :)
They also track forwards and prints. Prints are easy (they include a css @media print query with a bg image).
But forwards? I think this might be a combo between subsequent opens and different IPs/reffering URLs. However, this means that if I open my mail and re-read it from another computer, it counts as a forward. Any ideas on this one?
To summarize: Litmus Email Analytics says they can track email reads, skims, glanced/deleted, prints and forwards. How do they do it (skims, glanced/deleted and forwards)?
Tracking code: This is the code. You create a unique code for each list/campaign combination (so that you can track campaigns..) then you put the following html/css code before the tag of your email message.
<style>@media print{#_t { background-image: url('https://a6.emltrk.com/XX0000XX?p');}} div.OutlookMessageHeader, table.moz-email-headers-table, blockquote #_t {background-image:url('https://a6.emltrk.com/XX0000XX?f')}</style><div id="_t"></div><img src="https://a6.emltrk.com/XX0000XX" style="display:none" width="1" height="1" border="0" />
Test results:
With Gmail, print tracking works. Yahoo! somehow fails. Glances/Deleted actually works, I've tested.