Woo, got it to return relevant results, finally. If anyone ever does anything with the Amazon API, when doing an ItemSearch always include a BrowseNode.
Post any queries that get bad results.
I'm guessing this is caused by their API rather than this app... but it's actually faster to search Amazon the regular way than it is to use this "instant" version.
Yeah, I know--at least I didn't spend to much time on it :( Seems to be better if you set the category to books/music/movies. Problem is you can't sort the results with api if you search across all products. Even if you can sort the results, most categories seem to return a bunch of junk. Don't think it's the same search Amazon uses on their site.