I don’t get the attraction to being on LinkedIn or Facebook or Twitter.
I don’t need them to tell me I exist.
LinkedIn was a job hunting connection. You could have people who might be interested in you for contract work look at your credentials. It was interesting how some of the more obscure little thing might give you a boost. For example I once got a job offer simply because I had worked with the relative of someone who worked in another company. Her uncle was impressed enough with my work that he had mentioned it and when my name crossed her radar it was enough to tip the scale.