I have just uploaded the first public release of flacinfo-rb. It is available as a gzipped tarfile, a zipfile, and it is also packaged in a gem.

I have marked it as OS independant, as it should be, however, I have only personally tested it on Linux and OS X. If you want to try it on Windows and let me know if it works that would be great. I don't have a windows machine to test myself.