While I love the concept it seems somewhat flawed. If every URL needs to be manually submitted it is far easier for spammers than actual users. Especially if you need a handful of form URLs, is this intended for readers or authors? Because a reader likely just wants to see it or post it on their favourite form, I can't see them going around to a handful. If it is expected that the author does it than that is somewhat encouraging spamming forms.

That being said I like the idea, maybe submission could be made easier with a browser extension? Or you could crawl popular form feeds and become a sort of form aggregator as a form of crawling.

On the other hand how is this different than Reddit? You are basically aggregating links, except instead of providing a form you are linking to multiple forms. I'm not sure if that is better or just an inconvenience. Of course maybe just providing a functional search is enough to distinguish you from Reddit.