I used Puppet for a few years (and created a few modules for it https://github.com/puppetmodules). I switched to Salt a year ago. My main motivation were its simplicity (YAML+jinja), lower memory consumption, easier source code both to read and contribute to, and its support for both push and pull based architectures.

If you want to get a feel for how salt looks like when managing some servers and laptops you can take a look at my states: https://github.com/uggedal/states