Within the SQL Server 2005 BI product suite, where should metadata be
held regarding database objects for reporting? What I mean is if a
user is presented with a field called "start_date" then a definition
of what exactly "start_date" means should be provided on screen to the
user.

I am hoping to be able to create a single central respository which
can be sourced by all tools - Excel, Analysis Services, Reporting
Services, SQL Server Database Engine, Crystal Reports, etc.

I guess there will need to be two levels of metadata provided:

(1) SQL Server database objects
(2) Analysis Service OLAP cube objects

Has anyone had any experience of how best to store and provide this
metadata to report users in a data warehousiong environment?

Thanks,

\M