Bidirectional text support
There are a few languages that can be written right-to-left (RTL), sometimes intermixing with the left-to-right pieces, like numbers or English words. It is crucial for Middle East countries to support this everywhere. Some Linux console programs, like Konsole or Mlterm already support it, but there is ongoing work everywhere else. It would be awesome if Microsoft will lead the way and help with adoption.
See  and  for more information.