This article goes into better detail than the last posting on it. It talks about how the 10% improvement is in power output, and more importantly shows the range from 4-12% increase over the existing cell's output. This confirms that a cell that converted say 10% of solar input, would improve to 10.04% to 10.12%, but that number is still significant; particularly in utility scale installations.
The other main advantage is that existing deployed cells will improve with this film (sticker really) being applied. That seemed significant to me as well.
The article also goes on to say that since the average solar cell lasts 25 years, and the films are only guaranteed to last 20, there could be issues. Particularly when you consider the fact that the plastic film's durability and lifetime has not been verified by a third party.