Features
-Add maximum/minimum bit-rate control for VBR
-Get the encoder to use the rate of packet loss (more conservative pitch gains)
-Implement "packet terminator" with no overhead
-Improve error handling (with perror-like call?)

Long-term quality improvements
-Improve perceptual enhancement (including wideband)

Standards
-Complete Speex RTP profile
-MIME type registration
-MS ACM wrapper

ideas:
Peelable stream (double codebook, higher bands, stereo)
LPC from spectral domain
Better psycho-acoustics? Masking curve from Vorbis