potato sack" bundle is hiding something beneath the surface, much like the hidden ARG found in Portal after Valve updated it. A wiki page chronicles all of the discovered changes so far, which include some hidden glyphs and, if Razer equipment is detected, a message that reads "1...2...3...Drop That Beat (Like An Ugly Baby)." That odd phrase, of course, translates to "Secret Message."
Common speculation is that this has something to do with Portal 2 (the Razer tie-in lends credence to that). Nothing has been confirmed yet, and folks are still finding stuff -- if you discover more interesting info, feel free to contact us!