Tao: BOL is indeed misleading. You can try it if you have a test server at your disposal - run some queries, check that various indexes used show up in sys.dm_db_index_usage_stats, restart the server and then query sys.dm_db_index_usage_stats again.
You don't really get "no" information. You'll at least get a list of column names <g>. And you'll get an overview of what indexes were used during system startup. On my test database, startup apparently involved one scan of sysendpts and one scan of sysobjvalues.
If the server has some huge startup procedures, querying sys.dm_db-index_usage_stats right after a server restart might even be useful...
Nitpicking aside, this is a great question. Many people still don't know about this view. And judging by the distribution of answers, many people don't know that it's fllushed on restart either.
Edit: One more nitpick - this view is not available on versions prior to SQL Server 2005.
Hugo Kornelis, SQL Server MVP
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