Evaluating a first release like this is kinda silly. It's a road, not a destination. For a v1 (or a beta, which is what this really is), you're better off evaluating the road...

Regarding "tried many times over"... You mean like web search was before Google? Or MP3 players before the iPod? Or photosharing before Flickr?

I'm not saying I'm convinced this idea is a winner, but come on... Predicting failure for a startup is so laughably easy that I don't know why you'd bother, unless you just wanted to feel smug.