Wow, very cool!
The visuals are terrific. I agree that the voiceover sounds a bit muffled.
I think the 4 review snippets coming in from all sides of the screen provide a very striking effect --very well done -- it might be cool to follow this up by combining the three shots that follow ("The Origin of the Spinward Fringe Series", "Now available on Ebook", "For free") into one shot similar to that shot (or, have the first two shots -- "The Origin of the Spinward Fringe Series", "Now available on Ebook" -- come in as one shot and then "For free" come in on the same shot a couple of seconds later if you want to really emphasize the free element.).
Anyway, great job!