All tagged as they were by Sound Juicer on Kubuntu. So Artist, Album, Track Title, Genre, usually Year... all I would assume matter to the databasing. None are especially odd - examples of skipped tracks are "The Subways - Holiday - Young for Eternity" and "Be Your Own Pet - Becky - Get Awkward". Neither seem overlong, or have peculiar characters in.
None of the albums I am having this issue with have album art attached. The only one I did add art to is fine (and to clarify, does it count as embedded when if it's just cover.bmp in the same folder? I thought embedded would be coded into a file, or something like that).