Mingw-w64 version 3.0
- Required for GCC 4.8
- Much improved floating point math performance
- Improved MSVC intrinsics performance
- Addition of wide variants in C99 printf and scanf
- Partial C1X secure CRT support
- Partial MS Secure CRT templates for C++
- Vastly improved Windows 7 and 8 win32 API support
- POSIX-style Large File Support
- Winpthread: new library, pthreads implementation for Windows
- Winstorecompat: new library for Windows Store compatibility (WIP)
Version 2.0 focused on expanding Windows Vista/7 API support.
The project page has the full list of releases and more details.