Yes...

the software for use with Midi keyboards and other midi input devices
has been available in different forms & retail brands for well over a decade.

What's really new in the last couple of years
is a low cost performance to midi device marketed by "Sonuus"
that can quite reliably translate monophonic audio to midi.

ie.. you can now record voice and other monophonic acoustic instruments
direct into a mic and capture the midi signal as notation.

http://www.youtube.com/watch?v=bWaNlcXuGmI