Jack Franklin runs javascriptplayground.com which is a blog covering all things js, including testing, Backbone, Node, JQuery and so on along with cameo contributions from other developers.
In this presentation at Future Of Web Apps in October he talks about Gulp.js and how it has become so popular as a build tool whilst also demonstrating an install and common tasks.
With streaming, Franklin recommends this stream handbook on Github which explains streaming, in relation to Node.js in particular, from the basics and commands and runs through all the different types of streams.
Franklin explains briefly how Gulp removes the complexities and inefficiency of picking files off the disk for transformations, particularly on large projects before talking about streaming and absence of, more generally (go to 4:17).
If you want to dive straight into what Gulp is go to 6:38 starting with installation both locally to your project as well as globally and getting it to run on the command line as an automated task runner that works on streams using gulp.src to pull files into those streams and gulp.dest to write them back to disk.
