My guess is yes. I think it's worth trying, at least.

There may exist zillions of sites, but that in and of itself doesn't matter. If they can build a better product that can draw a large enough audience, that's important. I have personally looked around for tools like this, but haven't found anything that really kicks ass. Playing with their tool makes me optimistic -- they may be on to something.

I don't think they have to worry much about duplication. Building the product isn't the hard part, getting users is. Not sure if they'll be successful here, but if they fail it'll probably not be because of a clone.

Good point with the money, that almost certainly be tough. However if their product is useful enough and enough people use it they'll have an opportunity at making serious money.