The theme 'softWaves' created by Juliette Belin has been chosen as the default theme in the upcoming Debian 9 release. It came out on top from amongst 12 choices, after 3,479 Debian contributors cast their vote on which one they preferred.
In the post announcing that the chosen theme, Laura Reina and Niels Thykier wrote:
“We’d like to thank all the designers that have participated providing nice wallpapers and artwork for Debian 9, and encourage everybody interested in this area of Debian, to join the Design Team. It is being considered to package all of them so they are easily available in Debian. If you want to help in this effort, or package any other artwork (for example, particularly designed to be accessibility-friendly), please contact the Debian Desktop Team, but hurry up, because the freeze for new packages in the next release of Debian starts on January 5th, 2017.”
Debian 8 users will already be familiar with artwork by Belin as she was the creator of the 'Lines' wallpapers that were featured in the release. Debian 9, named Stretch after the Toy Story character, will be released in the first quarter of next year, currently slated for February 5th. You can find high quality versions of the artwork on the Debian Wiki.
Source: Bits from Debian