A couple of recent posts by Thomas Van Wal, SharePoint 2007: Gateway Drug to Enterprise Social Tools, and Dion Hinchcliffe, SharePoint andEnterprise 2.0: The good, the bad and the ugly seem to have re-started the SharePoint it's not really Enterprise 2.0 meme. These are both balanced articles and I agree with a lot of the points raised in them and certainly as with any application SharePoint has its strengths and weakness's. However one of the common criticisms of SharePoint is the rapid proliferation of sites upon deployment and I can confirm this from my own experiences, that in a large enterprise, within one year you can be looking at 1000's of SharePoint sites. But is this the fault of SharePoint? No this is a failure of deployment, it is a user failure.
SharePoint is no different to any other content management system and I've seen this same issue in every large content management I've worked with. There are two main reasons this occurs, firstly if someone does not manage the structure users will proliferate folders/sites in an uncontrolled fashion. In general people simply create what they need in that moment for their project. Secondly they restrict the access permissions, the assumption is that if they don't restrict access then someone will delete it/change it. Nothing creates silo's quicker than allowing users to control permission settings.
The implication in the 'proliferation of Sharepoint sites' comments is that if the companies had implemented a 'proper' Enterprise 2.0 tool set then this would not of happened. Sorry I don't buy this. It doesn't matter what the tool is if you don't invest resources in defining structure and allow users to manage permissions then you end up with a proliferation of silo's. I've heard of the same sort of proliferation of silo's occurring within wiki's based on Socailtext and Confluence, both of which allow user to create silo'ed wiki spaces. Even when the ability to set permission is inactivated or is not available, such as in MediaWiki, then you still need invest in wiki gardening to introduce and maintain structure as the wiki grows.
In the end it is not the tools but rather that those implementing social computing need to understand what they are trying to do. I'd guess that in many of the companies where silo's have proliferated it is more because the tools were introduced by people who understand technology not people/communities. In the end the whole social computing thing is not about the technology it is about the culture. If you don't understand the culture you are trying to create then don't be surprised if you end up with a mass of silo's.