As you can see in this example, if you don't consider this factor your system can be high quality but in appearance? It may resemble some stank ass. :0
I've included a couple of examples and good choices for alternatives to this unpleasant appearance.
OmniMount TRIA Adjustable 3-Shelf For ComponentsThree adjustable 6mm tempered glass shelves with shelf capacity of 30 lbs each
- Integrated cable management hides wires
- Use with or without flat panel
- Color: Black with black glass / Paintable and trimable covers
- Mounting: Single-stud / Easy to Install
Cheetah Mounts AS3B 3 Wall Mount Bracket
- Holds 70LBS
- Cable Management
- Aluminum and Glass Construction
- Easy Assembly
- Drywall or Stud installation
Of the two options I would choose the Cheetah mount. I've used both kinds and the Omni mount granted, has more invisible wire managment, its more of a pain to setup and change things if necessary. As a result, unless you're going to install it and never change your configuration of your hardware, I would recommend the Cheetah mount. It is cheaper to boot.
While I know many of you enjoy the backside of many things in this world, none of us like staring at the wires and crap sticking out of our Televisions, or any of our devices. Here's a couple solutions for a reasonable price without digging holes in your walls. Take your pick.