I've known Kent Agerlund for a long, long while and know that he's an expert on System Center 2012 Configuration Manager. Kent will also be speaking at the IT/Dev Connections conference this year in Vegas (check out Kent's sessions HERE).
When Kent released the 1stedition of his ConfigMgr 2012 book, it was met with great success and also high acclaim. Kent's 2ndedition of the book has been updated to included service pack 1 for ConfigMgr 2012. SP1 provided a LOT of additional features to ConfigMgr 2012, so a complete revamp of the original book is highly coveted.
You can order from Amazon.com here: System Center 2012 Configuration Manager SP1: Mastering the Fundamentals, 2nd Edition