Microsoft has published a FREE ebook of Introducing Microsoft SQL Server 2012.
You can download the ebook here.
Introducing Microsoft SQL Server 2012 includes 10 chapters:
PART I DATABASE ADMINISTRATION (by Ross Mistry)
1. SQL Server 2012 Editions and Engine Enhancements
2. High-Availability and Disaster-Recovery Enhancements
3. Performance and Scalability
4. Security Enhancements
5. Programmability and Beyond-Relational Enhancements
PART II BUSINESS INTELLIGENCE DEVELOPMENT (by Stacia Misner)
6. Integration Service
7. Data Quality Services
8. Master Data Services
9. Analysis Services and PowerPivot 1
10. Reporting Services