The local "artists" have been touching up this wall at the approaches to the Gladesville Bridge. The top photo was taken in May. Since then, the only bit of this wall with any artistic merit - the panel at the top left - has been painted over with black paint and a new pink and purple "squiggle" has appeared in its place.
The existing squiggles to the right have also been "improved" upon, if you can call it that. touches of red and white paint have been added as part of an ongoing project.
I still have no idea whether this is a legal wall or not. If the property owner has provided permission to do this, I have no complaints. I might not like the style, as it is not to my taste, but property rights are property rights, and the owner can do as they wish. If it's illegal, I hope the "artists" get busted one day and pay the appropriate penalty. I can't stand it when people think they have a "right" to interfere with the property of others.