Note that that bug is filed under the "backwards compatible" milestone, which is the absolute minimum for a 1.0 release. Barring drastic circumstances, you should assume that MSVC support will land before then.
However, Rust really needs Windows-savvy developers! If you can help, please do.
Yes. All development happens in lock-step on all 3 target platforms. Using MinGW, not Cygwin. Note that the windows implementation currently has some limitations: in particular tasks cannot unwind on windows, and all Rust executables require a MinGW installation at runtime."