Universal wishlist apps have been done many times in the past (wishli.st for example, financed by the Difference Engine accelerator a few years ago). On paper they're a grand idea - you have an easy revenue stream based on proved techniques through affiliates, the benefit to the retailer is obvious, the benefit to the user _seems_ obvious, so how could it fail?

The problem is simple: people like to choose presents for their friends. Wishlists aren't actually very popular. Solve that problem though, and you could be on to a winner.

You're also positioning yourself to compete with Amazon's universal wishlist. If you are going to pursue this project you probably need to find a niche or some differentiator, because right now Amazon's got more features and the financing to do a $2500 drawing every week between now and Dec 18th.

That's hard to compete with unless you can offer a very compelling reason why your service will be better and you make that reason obvious on your landing page.