Fedora 26 is in heavy development and the public beta version is expected to roll out on 30th May 2017. The final version is scheduled to be released on 27th June 2017. Fedora 26 will bring a slew of new features including Python Classroom Lab, GNOME 3.24, Golang 1.8, Python 3.6, enabling SSSD fast cache for local users, and more. You can see the complete list of new features at their Wiki page.
For now, the Fedora Design team has finalized a set of 16 supplemental wallpapers that will be released with Fedora 26. As usual the wallpapers are based of user submissions. As many as 92 wallpapers were submitted by the community. Fedora design team then used the Nuancier app to vote on the top 16 to include. A total of 257 Fedora contributors voted in a 15 days time. So here is a list of winners, courtesy of Fedora.
To download the full resolution images including all the submissions, head-over to Fedora Project page.