What realityking said, with an explanation...
Apple Lossless files are just that, lossless. The Apple Lossless codec stores a bit-for-bit copy of the original waveform, in a rather efficient way. No audio signal detail is lost. Thus, transcoding from Lossless to AAC VBR gives the same result as ripping the original CD to AAC VBR. Many users do this for their iPods, especially for non-Classic iPods.