• by Jordan Ayan , September 2, 2009

When Yahoo acquired email search company Xoopit back in July, most marketers probably didn't even take notice. On the surface, why would they? Xoopit's inbox search functionality is aimed at sifting through the pictures, videos and attachments a typical email user would receive from personal contacts. At the heart of that acquisition is an important concept that is easily forgotten in the email marketing world: Recipients may have a desire to view message content long after it was sent.

Many email marketers usually assume that they have a small window of opportunity to communicate with recipients, but it isn't necessarily an all-or-nothing or -- or an open-or-delete -- proposition. Cheap storage, along with organizational tools such as filters, folders make it easier than ever for subscribers to keep their inboxes orderly without simply hitting the delete key.

If recipients hold onto your old messages, it's likely that they hold onto other marketing messages too. If messages from your competitors are also being saved, it only makes sense to optimize your messages with keywords specific to your industry as well as your products and services to make sure your message will show up in related searches.

While it may seems obvious that marketing messages contain this type of content, as the connection between marketers and their audience grows, the natural tendency is to produce content for those already "in the know" -- which can lead to basic keywords being excluded. As a simple example, if your business sells clothing and shoes, make sure both words are included in the message. If you were to only refer to your product as "threads and kicks" in your messages, it's likely to be lost to your recipient.

A keyword-laden message can start to sound very scary - until you realize the approach here is very different than the keyword density usually reserved for Web sites. On a site, the goal is usually to rank high for a specific word or phrase, which must be used frequently in page copy. However, in the case of an email message, a keyword need only appear once to display in search results within an inbox. Making sure your most important keywords appear at least once in your message will accomplish what you set out to do. Keyword density in email lies not in repetition, but relevant variety.

If you are thinking outside of the inbox, relevant keywords in your email messages can drive additional traffic to your Web site. If your messages contain links to Web-hosted versions of your messages, search engines will index the content of those pages. Hosting an archive of those previously sent messages on your site will not only give prospective subscribers a way to sample the type of content they can expect to receive if they go forward, but can help your search rankings by adding additional internal links within your site to pages with relevant keyword content.

Before you move this email message into your folder of choice (or decide to leave it in your inbox forever), imagine that two months have past and a co-worker mentions the idea of using keywords in email. You remember reading about that somewhere, but you can't recall the exact source due to the sheer volume of industry newsletters you get -- so you search.

The bottom line: Increase the long-term value of your messages by simply making them a bit more dense. You may have long lost interest in what you promoted or wrote about and moved onto your next smart idea. It doesn't mean your reader has.