Wordpress is far and away superior to any blogging platform available on Ruby. It makes wonderful sense to write Wordpress templates in a somewhat more productive environment than raw PHP, then compile them down into something which requires no dependencies on the actual server. This gets you all of the many, many benefits of Wordpress (great plugin support! huge community! deploys at any commodity web host! SQL vulnerabilities patched weekly+!) while having your template development not hindered by copious amounts of spaghetti code.

It is also big news to folks who write a lot of templates, because something like this allows them to create a toolchain which spits out WP templates, as opposed to having to e.g. having a template framework that templates are built against. This means that they can do across-the-board updates much more easily. That's a huge win if, for example, you're a company that publishes 100+ templates and somebody reports an XSS vulnerability in a commonly repeated component of one of them. (I don't know if their other 99 templates are patched yet so I won't go pointing fingers, but suffice it to say this happened.)

+ Kidding, kidding. OK, mostly kidding.

I got the feeling this plugin was for people who need to— for whatever reason, be it work or otherwise— make a lot of Wordpress themes. In that regard, it's pretty neat. I wouldn't go so far as to learn HAML and how to use the RVM just to make a friend a blog theme, though.

Still, I dislike how the programming community jumps on someone for making something interesting— even if it's not immediately useful for everyone. I get the same feeling in reddit's /r/programming whenever a post pops up about someone using a "NoSQL" database. It seems the majority of comments tend to be people negatively criticizing the OP's choice instead of providing something constructive to the existing project.

I'm not a Wordpress fan, but for better or worse, there are Wordpress plugins that do many, many things. For certain sets of needs, you can just grap WP and several plugins, throw them together with a half decent theme and you're done. I don't advocate that, because I enjoy craftsmanship and elegant solutions, but some businesses can be built in weeks, not months, using WP at very low cost--maybe the cost of the theme--if you're smart enough to put the pieces together yourself (you are).