Thanks mchale, interesting stuff!

However none of the compression tools compared in the article were designed specifically for audio compression and the test only compares two parameters, file size and speed of compression.

There is a whole range of lossless compression schemes designed specifically for audio files which may be a much better bet for music archival since they are optimized for that purpose. They offer similar levels of compression but also include functionality such as metadata support that stores album/track information along with the datastreams and support for audio-oriented applications such as streaming (being able to start playing the start of a file before you've received the end).

There are a number of good articles out there summarizing and comparing them. Here is a sample from the Hydrogen Audio Wiki entry for 'Lossless Compression':

http://web.inter.nl.net/users/hvdh/lossless/lossless.htm
Includes an interesting graph of encode/decode speeds vs. file size on the All Albums page

http://wiki.hydrogenaudio.org/index.php?title=Lossless_comparison
A comparision focusing more on codec features and less on absolute encoding efficiency. Also features a table comparing most popular codecs based on their features.

http://members.home.nl/w.speek/comparison.htm
Performance Comparison of Lossless Audio Compressors - Compares file size, encode speed, decode speed for APE, FLAC, LPAC, WavPack, Shorten (SHN), RKAU, OptimFROG, LA, WMA Lossless. Updated 5-2003

http://www.bobulous.org.uk/misc/lossless_audio_2006.html
Lossless audio formats - A comparison of the rip-and-encode speed and album file size of six different lossless formats: uncompressed Wave, FLAC, WavPack, Shorten, Monkey's Audio, and OptimFROG. First published on 22nd May 2006.