What makes an essential Intranet?

An interesting PowerPoint presentation here from James Robertson of Step two Designs, who asks the question - "What makes an essential intranet?"

In the presentation which is from the recent Intranets 2011 conference James outlines what makes an essential intranet and perhaps more importantly how you measure the effectiveness of an Intranet.

This presentation is well worth reviewing if only for some of the screenshots of Intranets towards the end of the presentation.