Like it or not people are talking. They're telling each other what to buy, where to go, where to stay, how to get there, what they think. Huge networks with audiences measured in hundreds of millions have emerged in just a few years.

Britain is one of the most voracious consumers of social media in the world with the average net browser spending 26 minutes a day on Facebook, Myspace, Twitter, Bebo and LinkedIn. And their recommendations, comments and opinions are only going to get bigger.

Consumer opinion has a massive influence on purchasing choice. So how can big and small companies engage and benefit from the social revolution? Consider the story of "Sons of Maxwell", a small Canadian country music band.

During a scheduled flight on United Airlines, the lead singer's $3500 guitar was damaged. He spend the next nine months trying to get compensation from the airlines but with no success. So he wrote a song and recorded a video about his experience.

When the video was added to YouTube, the reaction was staggering: more than 3.8 million people watched it and some 17,000 left supportive comments. A large number said they would boycott United Airlines as a result. The video made its way on to mainstream media and when the song was released on iTunes it became the number one country track.

During the same period, United Airlines share price dropped by 11 per cent.

It may never be possible to quantify exactly how much revenue United lost because of the event but we can be sure of one fact: in a world without social media, the original complaint would never have mattered.

Some companies have started not only to understand the importance of social media sites but they are beginning to understand how to use them.

Look at another airline, Southwest, who started their social media strategy several years ago.

A team of 30 employee bloggers update their sites regularly and receive a healthy 70,000 unique users a month. They have 8000 followers on Twitter while their LinkedIn platform allows the company to connect to the business world.

YouTube is used to illustrate the human side of the airline like Dave, the rapping flight attendant, whose mid-air performances won him a TV interview with the US talk show host Jay Leno. When his rap at the shareholders' AGM appeared on YouTube, traffic to the Southwest website rose by 11 per cent.

There are five steps to customer engagement using social media.

1. Take time to listen

Find out where people are congregating, tune in to what they are saying and monitor the conversation closely. This information, if properly interpreted, should form the basis of tactical intervention which would have helped United Airlines. It should inform future social media marketing initiatives.

2. Who is talking about you on which social media channels?

You have followed the discussion, now you should be looking at segmenting your social media audience. Who is using what site? Once you know you will see patterns emerging. You will know how to respond and appeal to the various groups. Divide this audience into passive and active members of your community. Both are important.

3. Now get involved

Based on what you have learned so far, set up some short term aims.
Jumping straight in can look like blatant advertising which does not hold much ground in social media circles. Instead, start making friends with key bloggers, or relevant twitter users with large numbers of followers, or launch some basic social media apps. Make sure it's relevant, interesting, useful and genuine.

4. Engage with and start growing your audience

Now that you have a basic presence and you are active in social media space, there are various approaches such as content seeding, more in-depth social media apps, the growth of fan pages on social networks and increased activity through blog channels. This is the time to start running media specific campaigns targeting different groups and demographics.

5. Start providing spaces your audience can populate

Brands can now consider creating their own social network, blog or community sites. This gives the audience --who hang out in multiple locations across the web -- a place to come together, get involved and make a difference. With the rapid decrease over the last two years in the costs of building and running a social network, this is now a viable option that has massive benefits for customer acquisition and, more importantly, retention.

Ultimately social media is here to stay. Those companies who choose to engage properly will reap the rewards.

Those who don't could end up being the next United Airlines.