There is still no communications medium more important than email.

Back in the day, the most important way to communicate was to employ the town crier or the town gossiper. Then the printing press made things like the newspaper a good communication tool.  Then it was postal mail and then the telephone before arriving at   email.

Although email gained consumer adoption fairly recently (roughly 15 years ago), it has quickly become an indispensable part of our daily routine. Pretty much all your customers use email — and many check it over 5 times a day.

But how long email will remain at the top is uncertain. It has come under increasing attack by other communications forms like SMS, instant messaging, Twitter, Facebook messages, blogs, Gowalla, FourSquare, Google Buzz, and more. And last March, Nielsen Online reported that time spent on social networks surpassed emails for the first time.

It’s not surprising then that many people expect these other communication mediums to replace email. But with consumers directing all social media notifications to their inbox, social network use actually increases email activity, not replace it.

Maybe something will replace email one day, but it’s clear that email is still dominant and will not be giving up its top spot soon.

Given the importance of email, here are some ways to improve how you use email.

•    Personalize the content – don’t send everyone the same email. Segment your emails based on purchase behavior, demographics, and interests to increase targeting and relevance to your customers.

•    Keep communication brief and simple – consumers suffer from email fatigue. To make your emails stand out and work best, focus on what’s important to your customers and keep it short. Also, think of ways to reduce the total emails sent to avoid annoying recipients. Doing so will have your customers look forward to getting mail from you.

•    Use email to drive marketing – email is one of the most efficient and effective forms of communication. Email should be the focus point of your retention and acquisition strategies, and should also be used to drive customers to your social media efforts. Startups, especially, should focus on planning and leveraging email marketing. Companies that do a great job with emails include Groupon, Mint.com, and Gilt Group.