It's time to redefine the Lubuntu artwork. Now we grow and become a mature community, using our own themes and icons, not depending on 3rd party work (by other side, really remmarkable). With a look on GTK3 migration the Lubuntu look and feel will evolve on something more usable and beautiful, because that's the intention of design, making our lives and this world better, beautiful and easier to use to everybody.
The plan is finishing the Box icon theme for this release. A slow and delicate work. If you want to make additional icon for your apps, matching the Box theme, you can follow the Box style guidelines.