This is the same set of packages as that Core, only rendered with snappy instead of apt-get as the package management system.
[edit] FWIW, my task list this morning has "build custom base 14.04 image from ubuntu core".
I have asked on askubuntu a while ago, [1] and noone brought up this.
[1] Where do I start to create my own Ubuntu derivative? http://askubuntu.com/questions/483002/where-do-i-start-to-cr...