I recently attended Snappy Sprint Heidelberg, the first Snappy sprint focused on upstream and cross-distribution collaboration.
Snappy is a technology with an interesting history: initially started to provide App Store-like semantics (atomicity, declarative security) for the Ubuntu Phone project, it has since expanded to be a platform for desktop application deployment (e.g. VLC), as well as server applications and the IoT space.
There were a number of productive discussions with people working on Snappy itself, as well as folks from Fedora, elementary OS, KDE, and elsewhere.
At the start of the week, Snappy was technically usable in several different distributions, but only shipped fully-featured (in the main distribution repositories, with confinement, etc) in Ubuntu. Some great progress was made on AppArmor confinement in Arch Linux, and there is currently beta support for confinement via SELinux.
Providing a full-featured Snappy experience in Debian has its challenges, mostly relating to the lack of a default LSM. While AppArmor in Debian is supported and there's desire to have it be the default in "buster", Ubuntu carries a number of patches that add additional functionality not yet present upstream. I'm not sure whether pursuing getting those patches merged is more viable than waiting for SELinux support in snapd, however.
I've agreed to co-maintain the snapd package in Debian, and am excited to see intentions to support building snaps on a variety of distribution bases. While I do not expect Snappy (or Flatpak, or AppImage) to replace distribution-maintained software in the foreseeable future, nor do I feel that's a desirable outcome, I do think offering users freedom to choose to use software via these systems in a safe manner is critical.