Record that audio

Ambrosia Software, Inc. — utilities/freebies
From the makers of Snapz Pro X screen recorder software.
This explains it all:
WireTap is a free product for MacOS X 10.2 or later that allows you to record any audio playing on your Mac, saving it to a file for later listening or processing. This allows you to record news from Internet radio stations such as the BBC News, sound snippets from your favorite DVD movie, record the audio from a game, or even iChatAV conversations.
WireTap works using a simple tape recorder-like interface. Simply click the record button, and any audio playing through your Mac will be recorded to disk. WireTap can record any sound that is playing regardless of the source, so RealPlayer, iTunes, DVD Player, Windows Media Player, etc. are all supported.

Real encoding on OS X

Streaming Media, Inc.
Nothing for live streaming as far as I can tell but a step in the right direction. It has been a couple of years for Real on the Mac (not including third party encoding solutions such as Cleaner).
From the article:
RealNetworks, Inc. (Nasdaq: RNWK), today unveiled a beta version of its new Real 10 Export Plug-in for Mac OS X. The Real 10 Export Plug-in enables video editors for the first time to export high-quality RealAudio 10 and RealVideo 10 formats directly from Apple Final Cut Pro, Adobe After Effects, Avid Xpress Pro and more. Support for additional applications, including Adobe Premiere and Discreet Cleaner is expected this summer.