Please have a look at four new Best Practices Articles
SQL Server 2005 Predeployment I/O best practices                                by SQLISVPM team member Mike Ruthruff
SQL Server 2005 Deployment Guidance for Web Hosting Environments
by Alex DeNeui
Resolving Common Connectivity Issues in SQL Server 2005 Analysis Services Connectivity Scenarios
by Carl Rabeler
Implementing Application Failover with Database Mirroring
by Michael Thomassy, Sanjay Mishra