JohnDuncan:Use Apple Lossless. In preferences/general/import settings, select "Apple Lossless" as the codec in "Import Using" Also click on "use error correction", since this should get you closest to a bit-perfect copy of the original CD as iTunes can (though it's not guaranteed like EAC does, though it's Windows only so can't speak for it).Whether or not you'll notice the difference between that and 320kbps will largely depend on what you're playing it through subsequently - I'm currently stuck with just my Mac so there's no difference at all.
As John said Apple Lossless is the way to go, i also use error correction as well.ÿ
Whether or not you can hear the difference? i can on my iPod and iPhone when using headphones Senn PX100 and HD600.ÿOne of the first things i noticed was an increase in bass quality and quantity, which makes me wonder that a complaint about the iPod in general was a lack of bass, could it be crappy mp3s and not the iPod to blame? ÿ