Anyone that has considered or has actually deployed MOSS or WSS 3.0 is most likely familiar with the "Plan for Software Boundaries" article on TechNet.  Recently when researching an architecture for a customer I noticed some significant updates to this guidance document due to the release of SP1.  Most notable to me was the increase in the maximum number of documents per document library from 2,500,000 to 5,000,000.  That's great you say, more is always better, but what does it all mean?  Well it means that the guidance on SharePoint is being updated all the time as Microsoft works to optimize the platform.  Enterprises with a large number of documents would find this change significant in that it may alter their architecture when considering MOSS as a document management system.  I suggest referencing this document often and ensuring your architecture matches best practices as updates are released for MOSS.  Here is the link to the document in case you missed it above and some links to additional tools and resources that will help you architect and deploy MOSS successfully: