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

Enjoy