First of all, I had to do a double take when I first saw this image- I couldn't believe it was a negative!
The wonderful tones and contrast make me think of a lovely, velvety smooth bar of chocolate, that I want to indulge my senses in.
The repeating patterns of the architecture, create a wonderful rhythm and are aesthetically pleasing. None of the detail has been lost in the negative version, it's crisp and clean.
Compositionally, there is a lovely balance between positive and negative space.
Hmm...great shot, but looks more like a B&W than an negative, sadly. If it were a bit more "negative", I'd score it at the top. As is, I really like it, but can only give it an 8
There's another one in the challenge of the dome as well, and their's is just slightly better. I think because they inverted a coloured photo and you inverted a B&W one. Yours is still good though.