http://www.starwarsuncut.com/watchThe site explains it... Basically, they took ANH, cut it into 15 second segments, and then the internet took the segments and did their rendition. Then you take all the pieces and splice them back together. Now... there's some legal issues, so what you'll see are all the segments with recorded sound. The final cut will use the originally audio from the movie, from what I understand. But, if you run your dvd copy of ANH, and get it synced with the fan film, it works out pretty good. Some folks had some great ideas.
I'm loving this. I signed up for a segment, but mine didn't make the final cut. oh swells...