I'm confused about seeing the two lines in the boot log.

The memory report following is correct for 32MB though - the first line reports in bytes, the following lines in kB. If you divide 31928320 by 1024 you get 31880. The low 'free' memory count is because linux uses an aggressive caching strategy and does not discard old data immediately upon the premise that it may be needed again soon. Read here for an overview of linux page caching.
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Mk2a 60GB Blue. Serial 030102962 sig.mp3: File Format not Valid.