This is a rather misguided article. Unless everything has completely changed, Ruby is used for almost nothing in mainstream Linux. Bash and Python dominate "stock" system management code, and Bash and Perl seem to dominate for top-level add-on scripts written by a given sysadmin.

I've never even heard of any of those Ruby projects besides puppet, and I've only ever once installed Ruby- to support some obscure v0.03a library a developer wanted to try.

(Was a part-time sysadmin for 2 years)