I enjoyed the presentation and Andrew did well going over some of the best of was Sass and Compass has to offer. He explained the syntax of variables, mixins, and generally the SASS tools. He also covered Compass which has a great image sprite system built in, which I wasn't aware of. I've been using SCSS quite a bit for a number of years, so am already familiar with how it works, but the refresh is always good. I think perhaps if you wanted to reach the more experienced users, touching briefly on some best practices, SVG handling, and scalable architecture ideas could be great!
I agree 100% with Eric. John doesn't just talk from slides, his slides expertly and creativly demonstrate what he is talking about. This wasn't just a syntax talk either, but suggested styles and conventions to serve as the first of many important building blocks.
John has a relaxed, yet informative style of presentation that quickly gets to the topic at hand without dealing with extraneous filler. Even though John's examples were in PHP, he highlighted 4 good rules for building a function in any language. This was a good presentation for the beginner as well as a nice refresher for the more experienced developer. John not only talked about what to do, but also why to do it.