This was a very good talk: you gave a thourough introduction to Puppet, explained the different components and the workings. The live demo (without problems!) showed it all very well.
As a positive comment: you may want to emphasize the initial configuration of puppet (master/agent) a bit more, as it all seemed to go too smoothly on your test set-up. :-)
Nice talk. I can put this to use in a weekend-project.
Nice talk.
The concept and reasoning behind XMPP are interesting, and your (recorded) demo's definitely showed this.
For future talks: try to be more spontaneous. It's ok to prepare talks, but don't just read the text from a laptop. Interact with your audience. You obviously know a lot about XMPP as the Q&A showed afterwards, try to show some of that passion in your presentation by talking more "loosely" about the subject. :-)