$subj
http://www.freebsd.org/releases/9.1R/announce.html
- New Intel GPU driver with GEM/KMS support
- netmap(4) fast userspace packet I/O framework
- ZFS improvements from illumos project
- CAM Target Layer, a disk and processor device emulation subsystem
- Optional new C++11 stack including LLVM libc++ and libcxxrt
- Jail devfs, nullfs, zfs mounting and configuration file support
- POSIX2008 extended locale support, including compatibility with
Darwin extensions
- oce(4) driver for Emulex OneConnect 10Gbit Ethernet card
- sfxge(4) driver for 10Gb Ethernet adapters based on Solarflare
SFC9000 controller
- Xen Paravirtualized Backend Ethernet Driver (netback) improvement
- hpt27xx(4) driver for HighPoint RocketRAID 27xx-based SAS 6Gb/s HBA
- GEOM multipath class improvement
- GEOM raid class is enabled by default supporting software RAID
by deprecated ataraid(8)
- kernel support for the AVX FPU extension
- Numerous improvements in IPv6 hardware offload support.