Considering using this for the fragmenta cms at some point - it'd be nice for something like a blog addition to a main webapp to be able to register as a plugin, including views, styles and code. At the moment the code bit is the missing part of this, as code has to be compiled with the app rather than supplied separately. I think a plugin system for webapps would not be too tricky to set up and could have a very simple interface.
As the article points out, are still significant limitations with the support in 1.8 though, so it's not ready yet - Windows is not supported and the Mac OS support is broken. I'm slightly worried by the requirement to have plugins built with the same version of the go runtime, as that would complicate things significantly.