Your most loyal customers are not your most valuable ones.

A customer´s full value should include a measure of that person´s abillity to bring in profitable new customers.

According to V.Kumar, Petersen and Leone these customers are NOT your most loyal customers. In other words, your most loyal customers are not your most valuable ones.
More takeaways from http://weigend.com/files/teaching/haas/2008/readings/KumarWordOfMouthHBR2007.pdf :
-  A corporation that accurately targets those of its customers who are likely to make profitable referrals will earn a better return on its marketing investment than its competitors that do not.
-  Identify the behavior (not what they say,) and value of your customers and divide them into affluents, champions, advocates and misers.
-  Create targeted marketing that create more refferals by affluents, more purchases by adocates and more of both by misers.

Of course it´s important that focus is not only on increasing purchases, but also to make it easier for your customers to communicate positive information about your product/service. For CRM tactics this information is useful. But:

Yes, for growth, a brand needs to get more people to buy  - and buy more. And the brands that achives most growth are the ones who´s marketing efforts are focused on, and resulting in, getting more people to talk positivly about their product/service. Getting existing customers to market within their social networks is a smart thing to do – done right. But focus on simple refferals incentives towards existing customers alone is not enough. You need to focus on the whole market.

1. Start with getting at least 10% of your employees to become active advocates both in social media and offline. If you succeed with this you will create a tipping point for sustainable change.

2. Why should your employees advocate your product/service? Because you have identified an ideal -  a meaningful purpose for your brand. That both your employees and the market shares. This activates your employees, who will activate the market.

3. People don´t care that much about what you have to say about your product/service. The care about stuff they are interested in. So create interest plans with focus on making the lives of people better. Something that helps people, gives them beauty, serendipity,  give them stuff they did not know they wanted, amaze them, tell stories and entertain, give people the chance to help, help them meet new people, strengthen existing relationships, help them to be someone – to belong.

4. Based on this strategy:
Activate! Create different  - ongoing – solutions and find out what roles different tools (mobile, social, digital etc) can play in making this happen. (Social Media, Events etc)
...in 100% combination with
Advertise! Tell people what you do and with whom. ( TV, digital, in-store etc)

This means you should launch many solutions, measure and test live. Those that seems promising – advertise online/social. Those that deliveres according to business metrics – premium paid media scale. And here is the good part – brands are perfect for helping people express their identity , passions and plans. It´s TREMENDOUS opportunities for brands right now. Nail those interest plans!

The hard part? You need to
do it. You need to create something that is experienced so meaningful that it becomes a social currency. Creative passion and excellence, break the rules, extreme humor, provoking cause, co-create, use of celebrities and/or unconventional use of media is needed. (according to IPA)

Do this and your product/service will be talked about and growth will follow.