I manage intranets full time for 10 years. If a company deals with a lot of information that needs to be disseminated across all staff, then an intranet is an indispensable tool.
It can contain updated company policies, process and procedures as well as promotions, locations, scripting and other information which would be required by to be made known to employees.
I would be publishing more articles in future on this blog.
Meanwhile, please view below for the listing of published articles related to Intranets: