I'd take a stab at about 5-11 hours a day.
I usually listen to music at work all day (8 hours) and then when i'm at home on my computer in the evening and weekends. In other words, quite a lot of music.
Musical taste goes all over the board.
Frank Sinatra (whatever genre you want to put him in)
Alexisonfire (mix of screaming and singing rock)
Norah Jones (bluesish/jazzy)
The New Amsterdams (slow accoustic)
Deftones (rock)
i don't care who or what type of music it is, as long as it tickles my fancy