Linux 3.3 has not been released
Summary:
1. Prominent features in Linux 3.4
1.1. Feature
2. Driver and architecture-specific changes
All the driver and architecture-specific changes can be found in the [http://kernelnewbies.org/Linux_3.4_DriverArch Linux_3.4_DriverArch page]
3. Various core changes
4. Memory Management
5. File systems
6. Networking
7. Virtualization
8. Crypto
9. Security