Important: Please visit Power View documentation on office.microsoft.com for the most up-to-date content. Power View is now a feature of Microsoft Excel 2013, and as part of the Microsoft SQL Server 2012 Reporting Services add-in for Microsoft SharePoint Server 2010 and 2013 Enterprise Editions.

Power View provides intuitive ad-hoc reporting for business users such as data analysts, business decision makers, and information workers. They can easily create and interact with views of data from data models based on PowerPivot workbooks or tabular models deployed to SQL Server 2012 Analysis Services (SSAS) instances. Power View is a browser-based Silverlight application launched from SharePoint Server 2010.

See What’s new in Power View in Excel 2013 and in SharePoint Server.
 

Tutorials
Tutorial: Create a Sample Report in Power View updated for SQL Server 2012 RTM
Tutorial: Optimize a Sample PowerPivot Model for Power View Reports updated for SQL Server 2012 RTM

Samples
Power View and PowerPivot HelloWorldPicnic Samples for SQL Server 2012 RTM
Power View samples you can try yourself: Oil and gas, schools, toy sales, car and auto, and yes, picnic

Community Resources

 Microsoft MVP Jen Stirrup Talks Trellis Charts And Power View!
Using Database Images in Tabular BI Semantic Models with Power View, Dan English 
Visualizing Data with Microsoft Crescent book just out by Brian Larson, Mark Davis, Dan English, and Paul Purinicrosoft MVP Jen Stirrup Talks Trellis Charts And Power View!
Using Database Images in Tabular BI Semantic Models with Power View, Dan English 
Deployment Checklist: Reporting Services, Project Crescent, and PowerPivot for SharePoint