Death of the corporate portal?

Maybe thats a bit harsh ... but as a former corporate KM person I know how hard it is to encourage staff to participate in collaborative corporate portals. A couple of years ago I met a lady from a global portal software provider who was dispairing about how someone had set up a Linkedin group for their firm which attacted in a matter of days hundreds of members. In contrast getting people to join up with the corporate portal was like pulling teeth. We don't have to speculate long to understand why this is so. Just this past week I was speaking with my Italian partners Open Knowledge who have a project with another vendor to help them understand the nature of their LinkedIn groups and how they might be able to influence the members.

Just scouting the LinkedIn groups of some major portal software companies who no doubt have excellent internal portals (at least from a software perspective) I can see lots of informal groups with many members: e.g. Oracle (78 coporate groups; biggest with 1,000+ members); SAP (105; 3,000+); Microsoft (150; 5,000+); EMC (13; 2,000+); IBM (91;10,000+). Obviously not all are current employees but where is the corporate knowledge going to reside in the future?