This is notable since the innovative compiler infrastructure was just released last week and in the FreeBSD world, LLVM/Clang is the default compiler on x86 architectures rather than the GPL-licensed GCC. Aside from the more liberal licensing, FreeBSD developers found Clang builds packages quicker and uses much less memory.
FreeBSD 10 will officially use LLVM/Clang and deprecate GCC. Separately, there's also been attempts to build the Linux kernel with Clang and decoupling GCC from Debian and building Gentoo with Clang.
The LLVM 3.2 merge for FreeBSD was announced on freebsd-current. The most interesting features of LLVM/Clang 3.2 are covered in this article.