Anime was one of the first ice breakers for me and my husband, along with tokusatsu. If we hadn't had those things in common, we wouldn't have gotten married!
But all in all, anime as far as a lifestyle with dating was never a big deal for me or anyone I ever dated. If someone couldn't like me for my interests or hobbies, then I didn't want to date them in the first place!
Edit: and just now reading down (whoops), I think a specific forum for dating/anime is a neat idea, but the execution could take some time given the specific requirements. But nowadays it is easier to find a demographic interested in anime than it used to be. And there could be more people interested in finding others that want to share that mutual feeling!