I don't find much value in the LinkedIn timeline, for reasons well-described by this article.

However, LinkedIn has been of tremendous value to me as a founder of an enterprise software company. I see two primary areas for value:

1) Sales - LinkedIn allows me to quickly understand who I'm dealing with. Size of company, positions, org chart, etc. This is important information to know when trying to move along the sales process.

2) Recruiting - LinkedIn profiles are essentially a public resume directory. When folks are recommended or referred, I can often get a good sense of their resume by checking LinkedIn. This saves time for everyone when the connection does not need to be made due to lack of fit.