UPDATE (2017/08/31): we have moved away from using the Unity3d plugin in Jenkins. We wanted to have the ability to replicate more of the commands locally. So we have created the u3d tool to download/install/run unity from the command line. See u3d an open source tool to Download, Install, Run Unity from the command line. - Industries - News & General Discussion - Unity Discussions for more information.
The original Jenkins plugin is still there of course. It is maintained by the community of Jenkins users and developers.
Automating builds is a great way to be more productive and more professional.
At WeWantToKnow, we target 8 different platforms. Doing this by hand would be very time consuming. So we have lots of automated jobs. Currently over 100 jobs, with over 60 Unity3d ones.
Hereās a example of the jobs for one of our products, DragonBox Elements.
There are multiple ways to achieve this with Unity3d, for example using the Cloud Build service. Others might prefer to use a custom / personnal build server like Jenkins. For example if you cannot use Cloud solutions, or need more control of the build processes.
A few years ago, I developed the Unity3d Jenkins plugin (https://wiki.jenkins-ci.org/display/JENKINS/Unity3dBuilder Plugin), and this thread is open here for people to give their feedback, share their use cases or just network a bit.
Also, if you want to help improving the plugin or just working on tools related to build automation, feel free to take contact. I am open for hacking sessions, etc.