I subscribe to an awful lot of e-newsletters and e-marketing pieces. I am an email geek after all. What continues to amaze me is how bad most of them render through my preview pane.

As most of our clients have heard me say many times: HTML emails should be designed so that anyone who sees it through a preview pane with images blocked can still read the text, browse available links and know if images/video/audio are included.

This focus on content is important for any email. Although branding can enhance the performance of any email (according to ICONIX, emails marked with a visual icon have a 67% higher open rate!), your average receipient does not want to recieve an email that looks like some kind of “spam,” showing up with blank boxes and invisible images. They want a well written email (preferably sans fluff) that is relevant to their life (and sometimes even region) and gives them easy access to links, images, video, quotes, facts and other pertinent background information. Function over form, always!

We all know that people are overwhelmed with information. But a proper use of the preview pane can help your email stand out from inbox clutter. (Every little bit helps!)

We have long advised clients to write simple, factual, honest and concise subject lines that highlight the unique information contained in the email. But with the growing use of preview panes, the subject line may be getting less important. I haven’t seen a study yet, but I expect to see one soon suggesting that people open emails based on 1. from line, 2. preview pane and 3. subject line in that order. (I’ll buy you coffee if I’m wrong).

Preview panes are even more important in the B-B world, where the adoption rates for preview panes and disabled images are much higher, mostly due to the primacy of Outlook which is used by about 80% of the American workforce. And, as noted, content is king. So, make sure the recipients on your target list actually see your content by using the upper left quadrant–the prime real estate of any email–wisely. And please, don’t use cute web buttons for your links. Most of the recipients you target won’t ever see those so they won’t realize your email has all that fabulous content. (Don’t even get me started on flash and animation… that is for another day.)

Now I’m not suggesting you start ignoring the importance of a subject line–please, don’t start using words like “naked” or “free”–but I am reiterating that one way to improve the performance of an email is to make sure that recipients, who are often making split seconds decisions about what to read, can glance quickly at your email through their preview pane with images blocked and know its loaded with goodies.