The GCC code-base is still in stage four, which means only documentation and regression fixes are allowed. There's just four P1 regressions left in trunk, which means once those are cleared up, the code-base is at an intersection where GCC 4.6 RC1 can be tagged. Since the last status report, the number of bugs with this highest priority designation has dropped by five, so hopefully by the time of the next status report there will be the release candidate in hand.
While the P1 regressions are nearly cleared out, there are still 88 second-tier (P2) bugs, but those are not blocking the release candidate or final release. The P3 bugs, the least serious regressions that are tracked, have been wiped out with this status update after addressing all 10 of the remaining issues.
The GCC status update from today can be found on the GNU GCC mailing list. "Please be extra conservative what you consider a safe regression fix at this point."
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.