I uploaded the slide deck of my Entwicklercamp 2013 presentation on slideshare. The presentation is all about responsive web design, the history of it, what twitter Bootstrap is and what it provides and how to work with twitter Bootstrap in XPages.
The presentation is in german so Google Translate will be your buddy.
You can download a sample application that shows the basics of integrating Bootstrap in XPages that I provide under the Apache 2.0 licence.
A more complex example is the Collaboration Today project that you can download on OpenNTF.