The SQL Server Database Engine has published a SQL Server Columnstore Index FAQ wiki

The SQL Server columnstore index feature, code-named Apollo, speeds up data warehouse query processing in SQL Server code-named “Denali”, in many cases by a factor of 10 to 100. We’ll be posting answers to frequently asked questions here. For more information about columnstore indexes, please see Columnstore Indexes on MSDN.

There are 6 sections
Overview
Creating a Columnstore Index
Limitations on Creating a Columnstore Index
More Details on Columnstore Technology
Managing Columnstore Indexes
Batch Mode Processing

As additional questions arise they plan to add more content, so make sure to bookmark the page. Head over here http://social.technet.microsoft.com/wiki/contents/articles/sql-server-columnstore-index-faq.aspx to get all the details

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