Great Reference info on PowerPivot
http://powerpivotgeek.com/
PowerPivot and Powerview
http://channel9.msdn.com/posts/SQL-Shorts-PowerPivot-and-Power-View-Lifecycle-and-BI-Semantic-Model-BISM-Overview
SharePoint Config
http://channel9.msdn.com/posts/SQLShorts-Installing-and-Configuring-PowerPivot-Power-View-and-the-BI-Semantic-Model--BISM-
Blogroll
Denny Lee (DennyGLee.com)
http://dennyglee.com/
Mariano Teixeira Neto
http://blogs.msdn.com/b/mtn/
Official Excel Services Team Blog
http://blogs.msdn.com/excel/
Official PowerPivot Team Blog
http://blogs.msdn.com/powerpivot/
PowerPivot FAQ
http://powerpivotfaq.com/
PowerPivotTwins.com (aggregator)
http://powerpivottwins.com/
Rob Collie (PowerPivotPro.com)
http://powerpivotpro.com/
Ron Pihlgren
http://blogs.msdn.com/ronpih/default.aspx
Vidas Matelis (MVP)
http://powerpivot-info.com/