Levi Bryant is one of the most interesting philosophers writing at the moment, in my opinion. Like Harman, Bennett, and Morton, he rejects ‘correlationism’: the belief that whenever we talk about anything, we are only talking about how humans relate to that thing. He is a realist:
[Ontological realism] is the thesis that the world is composed of objects, that these objects are varied and include entities as diverse as mind, language, cultural and social entities, and objects independent of humans such as galaxies, stones, quarks, tardigrades and so on. Above all, ontological realisms refuse to treat objects as constructions of humans. (p. 18)
I think a perspective like this is essential for thinking about cities, infrastructures and public space. His The Democracy of Objects has just been published (2011). You can download a digital copy from the Open Humanities Press, or purchase a hard-copy. Great cover art by Tammy Lu.