For sometime a group of Program Managers from the SQL BI team have been working with a customer, Barnes and Noble, to produce a SQL BI solution for their data warehouse and analysis needs using SQL 2005.  The leasons learnt from all their work is being continually published to this website http://www.microsoft.com/sql/bi/projectreal/default.mspx in the form of webcasts and whitepapers.  With so many new tools and functionality to play with in SQL 2005, I have found their work (what I've seen of it so far), to be invaluable.