XLD
I've been using this software recently for CD rips and transcoding (multi core support), I must admit I'm very satisfied with it especially now it supports Accurate Rip. The other one for the Mac apart from iTunes is 'Max' but I don't seem to get on as well with it.
http://www.macupdate.com/info.php/id/23430/x-lossless-decoder
Tutorial for accurate CD rips on Mac OS X
http://jungle.sk/XLD_Tutorial/