One of most underestimated things within placing a SharePoint Portal at a customer is governance. Governance is a set of roles, responsibilities, processes and rules which are defined within the enterprise to guide the enterprise in using the Portal and al its functionality (standard or non-standard). a see a lot of Portals placed at customers without any consideration regarding governance. Fortunaly within the company i'm currently working for, this is not anymore the case.
There is a lot of information to be found around governance and if you are involved in large Portal projects as an Architect then this list of information can be considered as a must read!!
Thanks to Bart Wessels (he mentioned it at his blog today) a link to a sample template for a SharePoint Products and Technologies goverance plan.
Also Joel Oleson predicts a lot of good stuff about governance. I already mentioned it earlier...follow one of his sessions about this subject. You can find some interesting stuff regarding governance at his blog like:
Also a lot of information can be found at CodePlex Governance.
Robert Bogue has put also some stuff online regarding SharePoint Goverance. This is divided in part 1 and part 2.
Mauro Cardarelli wrote some interesting stuff around this subject. He has put some rules for a governance framework for MOSS online.
There is also a whitepaper available at Microsoft which describes compliance-related features and extensibility opportunities within the 2007 Microsoft Office System that can assist you to create a correct governance plan.
You will also find some interesting whitepapers at the blog of Kailash regarding Information architecture in SharePoint Server 2007, SharePoint Products and Technologies customization policies, sample governanceplan and Logical architecture model for corporate deployment. All these whitepapers can be found here.