I'd rate my own preferences as
1. Classical
2. Jazz
3. Pop
4. World / New Age
Broken down into:
1a, 1b, 1c, 1d, 1e. (tied) Baroque, Classical, Romantic, Modern, and Contemporary
1f. Renaissance and Medieval - though I hope to get that up to tied with 1a-e soon.
2a. 1945-1970
2b. 1970-present
2c. 1920-1945
3a. Rock
3b & 3c. Blues, and Country (especially prior to c. 1980; aside from Johnny Cash, very little later than that)
3d & 3e. Folk; and Techno and electronica
4a & 4b. Indian Classical Music; and other "world music": i.e. Nonesuch's Explorer Series; the music of Islam, etc.
4c. World music fusion: i.e. Putumayo Presents, etc. (most of this really should count as pop)
4d. "Pure New Age": i.e. Enya, Yanni, Clannad, etc.
Ranking each of those subcategories relative to each other according to about how much time I'd guess I spend listening to them:
A: 1a, 1b, 1c, 1d
B: 1e, 2a
C: 1f, 2b, 3a
D: 2c, 3b, 3c
E: 3d, 3e, 4a, 4b
F: 4c, 4d