Here are my demographics: 22 year old female living in Central Florida. Recent college graduate with a Bachelors of Business Administration with a concentration in marketing and a minor in finance (say that five times fast!) who is now rethinking the whole thing. Avid reader. Toying with the idea of possibly writing something, but who knows. Whether it's from the young adult, fantasy/sci-fi, horror, or romance section, the books I read must have a supernatural/paranormal thing going on.
1. What kind of covers do you like? Unusual colors tend to draw me in. Reds, blues, grayscales, and browns tend to be a bit overused, so when there's some bright purple or orange or a nice green, I'll be drawn to it for the uniqueness. Cover models are fine as long as they don't look slutty (for women) and have their shirts on (for men). I'm not into a lot of skin on my covers. Tattoos are case by case -- if the character has one that is important, it should be there; if it's there for design sake, ehh. I often find that when you see a cover models whole face, he or she never looks like how the main character is described (and how I see him or her in my head), so I like it more when a characters face is hidden/turned away/cut off/etc.
2. How much detail should be on them? "Maybe three things maximum on the front cover – character, setting and symbol. I’m happy to have a very detailed setting, but would prefer more anonymous character models." Tez answered this one perfectly. When there's too many elements, the covers start looking more like collages and less like art work.
3. Do you prefer characters or symbols, and why? Both. I like characters on covers, but the symbols help tell a story. If there's just a cover model and an abstract background, you don't really learn anything. If there's a cover model, some weapons, a creepy thing in the background, and an abstract background, it starts to tell a story before you even open the book.
4. What don’t you like on covers? I'm over scantily clad cover models. No one runs around fighting evil in stripper-wear or shirtless.
5. What would you prefer in digital artwork? Characters, or something to do with the story? I really like when there's a seamless combination of photography and digital artwork. My favorite use of digital artwork is when abstract swirls or patterns are used to blend different parts of the cover together or evoke a certain feel, like how orbs and swirls of light could help evoke the feel of magic.
6. Links to covers you do like, both digital and ‘normal’.
My favorite part of this cover is the abstract digital background. Without it, the cover would just be a model and some buildings in the background. I feel like the background draws the eye in and gives the cover a feel that really fits the book. 
I like how we don't see the cover model's face, which allows us to envision the character however we'd like. My favorite parts of the cover are the green color and the overlay of the paisley-like patterns. It's a subtle addition that gives the cover a little character. 
This is a perfect example of a cover not needing mantitty. I can see the guy running around fighting evil exact how he is. He won't waste an extra ten seconds pulling a shirt on over those crazy muscles. Plus, this cover has a shine that doesn't translate over the internet that gives it a very mysterious quality. 
Another example of how not seeing part of the cover model's face actually works. Plus, the necklace is front and center, an object that is actually important to the story, and not random. Plus, the rest of the jacket is black with a gray paisley pattern overlayed that makes it feel a little more refined.
