To be LinkedIn or not?

As someone who is often described as a "serial networker" I am often asked whether LinkedIn is useful?
It is often said with a "sense of doubt" and it takes me back to the same feeling I once shared.
The truth is, using LinkedIn was one of the best things I ever did.
Like most things you have to take a little time but by using its strengths you will never regret it.
It has the power of a Web and Search Engine combined.
It made an early and significant Impact on my success.
I often hear people say "I am too busy" followed by time less well spent doing something else.
Its not like Facebook.
It does more than Twitter.
You do not have to do it but then I guess success is never compulsory!

http://uk.linkedin.com/in/derekcarpenter55