10 Best Intranets of 2009" list along with a good analysis of the trends he is seeing in the space. This extract of a much larger 473 page report gives some interesting highlights that anyone looking to roll out an enterprise intranet solution should read.
According to the article, empowering collaboration and providing social networking tools for the corporate user base seem to be gaining momentum. While there are many in the industry who feel that enabling a workforce with FaceBook-like functionality is counter productive I would argue the opposite. If used properly, social tools can provide the foundation for knowledge share and become a tremendous asset for productivity. Also, by looking the other way when it comes to this trend companies are ignoring that fact that if they don't provide a secure, managed platform the user community will eventually create their own.
Another interesting call out from Mr. Nielsen's report is the apperant consolidation of technology being used with SharePoint becoming more and more dominant in the space. In fact, the article points out "fully half the winning intranets used SharePoint".