How do you use Social Media?

For the past month I have been looking deeper into Social Media, trying to get a better understanding of the various services available and also to see how and why individuals and businesses are using it. I was already a casual user of Facebook, Twitter and LinkedIn but have now started blogging and using other services such as Foursquare and Klout to get a better idea of what is available and what impact they have.
One thing that has really hit me is the amount of time people and businesses are spending on Social Media and often without a clear benefit. Personal use seems to focus on Facebook with some people also tweeting and making business contacts via LinkedIn. Fewer people seemed to be aware of Foursquare but I can see how this service could grow if the number of users increases, possibly on the back of inventive use of its facilities by businesses.
I have been looking at the output of certain Tweeters who are, by certain measures, deemed to be the elite of Social Media and their approach and content can be very different. Some have genuinely interesting Tweets and I can understand their success. Others seem to Tweet very similar information and it makes me feel they are using a database of Tweets including the words ‘Social Media’ which are submitted randomly by a piece of software.
My observations have also made me realise that, not surprisingly, you need to be very careful choosing a Social Media expert to advise your business. The output of some selling themselves as experts seems very naive and it makes you wonder what advice they are giving their customers.
The understanding and use of Social Media across businesses is very variable, some Directors just give you a blank look when you mention Social Media but it is clear other businesses are running huge and very successful campaigns.
Overall I get the feeling it is still early days for Social Media and I will be interested to see how use of services develops. I get the feeling the current use of multiple services is too time consuming and unsustainable which leads me to predict the number of services will contract over time as each expand their facilities to cover the strengths of their competitors. The problem is knowing which horse, or horses, to back. Which service will be the ‘VHS’ and which the ‘Betamax’ and will you and your business direct your time and effort in the right direction?