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GitHub User: tomciopp
When you see any version of "$" it will refer to a global variable in Ruby. The global variable "$*" refers to the command line arguments passed into the program. (In this case the urls of the rss feeds.) It is not the same as simply declaring an array.
If you are going to use pow at all you should be using the powder gem, it will make your life 1000% easier.
There is an error in the notes for pjax_rails. The manifest file should just be
//= require pjax