Consider the pros and cons of each placement:
1. If pointing down to the player, then you will get some nice stereo sound when you're right there playing. But if pointing out, you'll have speakers RIGHT AT YOUR HEAD level. Do you want that?
2. For music it's best to have speakers widely spaced out, for maximum stereo effect. So even if they are mounted in the marquee and pointing out, if you're sitting across the room, you're not going to get much stereo seperation.
My suggestion: Mount them in the traditional way, but build in a bypass connection so you can hookup external stereo speakers to the whole system, and place those speakers far apart, as you would with the standard stereo/cd player/home theatre setup.