You really need to do a fair comparison by comparing this to other interpolation algorithm and show the results that are the same size. Start with the same picture and run it through photoshop with algorithms like nearest neighbor and bicubic. Compare those results to the Gigapixel results.
The bottom line is this. Interpolation makes educated estimates to create data where none exists. Some algorithms may do it a little better than others depending on the characteristics of the picture. Some can make pictures look "better" than others, but looking better doesn't really increase the amount of information.
I haven't used the Gigapixel algorithm but I've used a bunch of others. There is no substitute for a higher resolution image sensor. Of course with most cell based cameras, that does little good as pics are decimated before they are transmitted.