The SQL Server 2005 Database Mirroring with SharePoint Products and Technologies whitepaper has been updated and available for download at http://go.microsoft.com/fwlink/?LinkId=83725&clcid=0x409.  Revisions include information on configuring failover with SharePoint Products and Technologies using SQL Aliasing, content database limitations and more.

SQL Server 2005 Database Mirroring posts on this blog:

SQL Server 2005 Database Mirroring and Windows SharePoint Services 3.0/Microsoft Office SharePoint Server 2007 - Part 1 (Introduction, Overview, and basics)

SQL Server 2005 Database Mirroring and Windows SharePoint Services 3.0/Microsoft Office SharePoint Server 2007 - Part 2 (Configuration)

SQL Server 2005 Database Mirroring and Windows SharePoint Services 3.0/Microsoft Office SharePoint Server 2007 - Part 3 (Failover)

Cluster or mirror?