Something worth thinking on with SQL 2008 is the Filestream functionality. I am told reliably (an MS source) that this was developed specifically with SharePoint in mind. The idea being quite lean databases with all the BLOB objects from the document libraries and other content being seperate to the database itself. SO all the Pro's of having a CMS and all the Pro's of having a Fileserver with none of the cons. Slightly off the DBA track I know but as it's a huge product at the moment its worth considering if you are spec'ing or designing backends for this kind of system.

D