iTunes ignores ID3 version 1.x tag information and embedded images in MP3 files. For those of us who wrote 1.x tags first and then used 2.x tags for “long string” support, we must use a tool like MP3 Tag Tools (on Windows) to copy 1.x tags to the 2.x fields (use the F6 key in MP3 Tag Tools).

Album cover art is another problem with iTunes. According to onetipaday.com, “The problem is though, iTunes doesn’t add the artwork to the actual ID3 tag within the file that is read when other applications play your mp3s, so the artwork is only visible to iTunes.” For more information, see:

http://www.onetipaday.com/2006/12/31/
    how-to-add-itunes-artwork-to-mp3-id3-tags-using-itunes/

See also “ iTunes: Working with ID3 Tags” here:

http://docs.info.apple.com/article.html?artnum=88186