The answer to this question probably deserves a blog post. But, as mentioned by @willejs here (https://news.ycombinator.com/item?id=7646496), Jenkins has a well established community of plugins and plugin writers and so, is quite extensible. Go has good visualisation and good modeling capability, allowing you to model complex build and deployment workflows using a combination of tasks running in parallel and serial.

Both have many more pros and cons. To do justice to it, it needs a blog post. Let's see. Maybe I'll write one soon.

EDIT: This mailing list post has some more information: https://groups.google.com/forum/#!searchin/go-cd/jenkins/go-...