Black paint would look great and be very dramatic. But I would mirror the shelf backs and leave the existing wall color.

I like the white,
Don't do stone or tile in the back paint it if anything

If you want texture inside the cabinets look at grasscloth.

I love the grass cloth idea!!!!

That look like more of a chocolate color than black, and notice I have black marble around the fireplace. Thoughts?

It may be more of an expresso which is a very popular furniture finish now. It would be a bit softer than black. Take your furnishings into consideration too. Would your sofa and chairs look better with black side and coffee tables or the softer expresso or chocolate ones? Here are some black built-ins flanking a light wall and FP. If your cabinetry is plainer than the FP you could go that direction making the fancier FP stand out. If you want to go all black you might add some trim pieces to the cabinetry that tie all three items together as more of a decor unit. I'm thinking the flat panel on the top of the side cases could be trimmed with another of the little center appliques.Have you gone on one of the major paint company sites and used their app to see the color applied to your photo? That would help you decide. Black will visually soak up a lot of light in the room. Do you have lots of natural light coming in opposite the FP? Not trying to discourage the black, but make sure you know the effect you'll get with it. My first concern was the grasscloth idea, but other things might need to be addressed. It could be a lot of dark which could unbalance your room. Post pix of the rest of the space and give the dimensions. I'll be glad to help you work through the best outcome. It is a lovely FP so no worries!

Looks like a fairly small space, black will minimize a small fireplace and darken the room. I would take everything off the mantle, walls, and shelves. Then stand back and consider how to dramatize it. It is nice now... but could have so much more impact with lighting *led and really interesting articles that catch your eye..

The picture is deceiving. The room is huge with 25' ceilings. The room is about 30' X 35'.

In that case, as long as the natural light is sufficient, go for your black! I do agree if there is no lighting in the cabinets it would be a worthwhile installation. Illuminate the art with a controlled wall washing can in the ceiling . They make them for that special purpose. Just noticed the shelves on the left seem to be doubles while those on the right look like singles. Have you stacked extra shelves on the left? Balancing those would be a good thing.

If you were just to paint the bookcases black and leave the white in the center, it would make the center stand out and appearing more towering.

If you want to paint the bookcases and trim black or dark, I would paint all the woodwork shown and use the same base color for the fireplace but marbleize just the fireplace surround from the floor to the ceiling. Below is a picture of faux finish marbleizing. I'd also put some shelf lights in the cabinets. Also consider perhaps using a mirror where the picture is to bounce more light and mercury glass candle holders and perhaps vase twice the size of the lights that are there now. To balance the height of the fireplace on each side, consider using series of square paintings horizontally on each side, in the center of each area instead of sitting on the top of the bookcases.

The paint colors in your room actually look pretty dark already. I would suggest not painting the bookshelves AND the fireplace black. That's going to make your whole room very dark, which can make the room feel much smaller. I also don't think the shelves are deep enough to add faux stone or tile - I would leave those the same color as the bookshelves. If you want dark bookshelves, I would leave the fireplace a lighter tone to provide contrast. You also might want to choose lighter wall colors to break up some of those dark tones.

I would try to mimic the look in the photos decoenthusiaste posted. They have some great ideas about using espresso over black tones. And their photos display the effect I'm talking about. In each of those photos, the rooms have light colored walls and fireplaces to create contrast and break up the dark spaces.