You don't have to know about yum, apt or whatever package manager your hosts use thanks to synapse-agent's abstraction layer.

Except, of course, that a sysadmin who doesn't know this is not a sysadmin. And someone who tries installing the same package across different operating systems is going to be in for a shock when it turns out that they have the same name for different versions, or different names for the same version, or completely different ways of configuring it.

This looks neat, but I don't see anything that says they have learned lessons from puppet, bcfg2 and cfengine.