For Boston, my favorite would be the workflow in Jenkins talk that will cover the new workflow job type Jesse and I are working on. As of this writing it is still very much a work in progress, but that talk is our way of putting a stake on the ground that we WILL have something we can talk about by then. There's also some talks that describes how they've put together pieces (including Jenkins) to create a broad automation, such as Distributed Scrum Development with Jenkins, Vagrant, Fabric and Selenium and Moving Existing Enterprise Systems to Continuous Integration and Deployment with Jenkins.
For Berlin, it turns out that we have steller line up of the speakers far beyond my expectation. You have a number of key community contributors/developers like Christopher Orr talking about how he does mobile build/test/deploy, or Vincent talking about literate plugin. I'm also looking forward to the Puppetizing Jenkins Pipelines from Julien Pivotto, which (if I understand correctly) is about deploying Jenkins and its jobs through Puppet — That is something I notice many people are very interested in nowadays.
All of them are looking forward to meeting you and hearing your thoughts and feedbacks, and I'm sure this is going to be a great learning/networking oppotunities.