Released a few days ago, I am happy to announce that LLVM and clang 3.1 are already available in the Debian archive in Unstable. RC versions were already available for the last few weeks in Debian experimental. They are very likely to be part of wheezy.
We will soon try a new rebuild of the Debian archive with the version 3.1.

Talking about clang, a couple of months ago, I proposed a GSoC project to extend the Debian infrastructure in order to use clang instead gcc to build Debian packages. The goal is not to replace gcc but it is more about building packages with a new compiler.

With Paul Tagliamonte as co-mentor, Alexander Pashaliyski is going to work during the summer on this subject.

The final deliverables should be:

• Build services modified to be able to use clang instead of gcc/g++
• Integration into the Debian infrastructure (buildd.d.o, and similar services)
• An easy way to switch of compiler between gcc/g++ and clang
• A way to build a package with a different compiler (gcc, clang, intel compiler, etc)
• Time permitting, a fully clang-built Debian installation

For now, Alexander is working on an installation of the wanna-build and buildd services in order to have a dedicated testing environment.