Hello, there are two issues with the current NixOS page.
https://distrowatch.com/table.php?distribution=nixos

1) Distro always rolls with a unstable version, kinda like a rolling release. I think it should be added to releases. You can find the info at following links:

https://releases.nixos.org/nixos/unstable/nixos-19.09pre181629.ae71c13a92f
https://github.com/NixOS/nixpkgs-channels
( it's the nixos-unstable branch on the git repository, main branch )

2) Logo is outdated. Current high-res logo that I could find from https://nixos.org :

https://nixos.org/logo/nixos-logo-only-hires.png