The Opus lossy audio compression codec for real-time applications on the Internet that's comprised of the SILK and CELT codecs is now in beta form for version 1.1.
Opus 1.1 came into alpha form at the end of last year and featured quality improvements, optimizations, bug-fixes, and an experimental speech/music detector. The Opus 1.1 format is now in beta form as of yesterday.
Opus 1.1 Beta was announced on the mailing list
and there's also a new demo page for the audio technology. Opus 1.0.3 is also now available with fixes plus back-porting the Opus 1.1 surround API.