Red Hat's Jakub Jelinek issued a new status report on the progress of GCC 4.6. The P1 regression count is now at zero, after the last four bugs were corrected in the past week. There have also been seven P2 regressions fixed, but three new regressions of P3 status discovered.
With the P1 regression count zeroed out, a few minutes later the first release candidate was released by Jakub. Assuming there isn't any bad feedback about GCC 4.6 RC1, the final release should not be too far out.
The GCC trunk is now already being focused towards GCC 4.7 work.
GCC 4.6 will be released head-to-head against LLVM 2.9, which is a major update for the Clang and Low-Level Virtual Machine folks and that final release is coming in early April.
GCC 4.6 delivers Intel Sandy Bridge AVX support and other Core i7 / Core i5 / Sandy Bridge optimizations, support for the Google Go language, greater C++0x support, link-time optimization improvements, a -0fast optimization level has been introduced, inter-procedural optimization improvements, experimental support for the C1X revision of the C language, ARM architecture enhancements, AMD Bobcat CPU support, and many other changes.