I learned a tip how to get email opened from a colleague while co-presenting for the Direct Marketing Day at Your Desk from Target Marketing. So with credit to Carolyn Goodman at Goodman Marketing Partners (www.GoodmanMarketing.com) I share the following about the importance of design, and how that interacts with the email preview pane. A signficant number of email users are able to preview email without opening it. I do it all the time. You may, too.
Some of us preview the email horizontally, across the top. Others of use preview on the right of our screen so the left side of the email shows.
Nearly 40% of email providers block images by default (mine does). So often I see a big blank spot on an email with a red x.
Knowing this issue, you are advised to design your email so that it begs someone to open it by merely looking at it from the preview pane. Make sure the top of it has text that will draw someone to open it. Make sure the left column of your email has the same copy to show. Having a pretty picture in those spots likely won't show since the images are blocked.
Use strong sales copy in those email "hot spots" and you might have a better open rate. Since often when readers preview the email, if nothing is there to grab and compel them to open it, you've lost your split second chance to at least get it opened just because of a preview pane.