"o.k...GO?" is a really inventive idea for the negative image challenge. You have defiantly meet the requirements of the challenge.
Overall the image is good but the twist is the best part of the shot. I like the placement of the subject. Also the layers created by the background helps the shot. I just wish the sign was straightened to match the top of the frame, but that is just my opinion you may have been going for it to be specifically not straight. I also might have tried a tighter crop on both the top and bottom of the shot. A nice tight shot might have helped people stop and pay attention to what you were really saying.
Not really liking the "Muddy" look of the sign, just looks wrong somehow. That and the composition is a bit questionable. This would probably have looked cool with an ultrawide lens shot from the ground with a car driving past you on your left side... Just an idea.
This image might be improved by a levels adjustment after inverting it, to make it look less somber. It also looks a bit tipped to the left. Clever title.