Even tough the Transcoder is made for live streams we’ve found it is easy to configure to record mp4 files with AAC audio and h264 video.
This is a great achievement because these mp4 files can be played directly on iOS/Android devices without the need to pass the flv/mp4 file trough ffmpeg.
Wowza is also the 1st media server to do this, FMIS produces mp4 files with with Speex audio while Red5 produces only .flv files ( None can be played on iOS/Android).
Detailed tutorial on how we’ve set it up here: http://avchathq.com/blog/recording-mp4-filesh-264-and-aac-with-hdfvr-and-wowza/