AAC codec for 68k?

[da9000]

Really quick here (I can talk for hours about codecs/compression/audio/video):

Ogg and AAC are quite modern. Ogg is better at most bitrates BUT low bit rates. At least that was the status as of a couple of years ago (been really busy with other things lately, hehe).

Here are some great links:
http://www.rjamorim.com/test/index.html
&
http://www.rjamorim.com/test/multiformat128/results.html
&
http://www.hydrogenaudio.org/forums/index.php?showtopic=21904&hl=
http://www.hydrogenaudio.org/forums/index.php?showtopic=36465
http://www.hydrogenaudio.org/forums/index.php?showtopic=35438

http://cec.concordia.ca/econtact/9_4/tsabary.html
http://www.soundexpert.info/

More at:
http://en.wikipedia.org/wiki/Comparison_of_audio_codecs
http://www.doom9.org/codec-comparisons.htm

And lossless codecs:
http://wiki.hydrogenaudio.org/index.php?title=Lossless_comparison
http://www.hydrogenaudio.org/forums/index.php?showtopic=55868