Add the "Mini-Album" primary type.

In Asia, particularly Japan and South Korea, CD albums which have up to 6 songs are called Mini-Albums, and 8+ songs - Full Albums. In iTunes Mini-Albums are set as EPs. For reference the Japanese wiki has this entry for Mini-Albums: http://ja.wikipedia.org/wiki/%E3%83%9F%E3%83%8B%E3%82%A2%E3%83%AB%E3%83%90%E3%83%A0

Add the "Maxi-Single" primary type.

Singles are usually up to 2 songs. Sometimes, in Asian countries, Singles which contain 4 songs (2 songs + their karaoke versions) are called just singles. Singles with more than 2 songs are called Maxi-Singles, apparently in West as well: http://en.wikipedia.org/wiki/Maxi_single