My CM Briefing for this month discusses who should own the intranet. To quote:

One of the first challenges when establishing an intranet is to determine who should have overall ownership of the site, and where the intranet team should be located. While the responsibility for driving the intranet must be given to a single business area, this group must be located within the right area of the organisation if the intranet is to succeed.

This briefing explores a number of common intranet owners, and discusses the pros and cons of each group. It then presents some general guidelines and approaches for selecting where to place the intranet team.