1. There are other sites doing this better and they have far more than just a landing page.
2. Are you holding user data? If so what about hippa compliance?
3. Your differentiating factor: "We scrape medical forums, blogs, twitter, facebook, etc (all the social media avenues) and add a layer of intelligent semantic analysis to bring you the best information relevant to what you have (or just the hottest news if you don't have anything)."
Simply put, I dont believe that you have one single bit of this.
4. Why would I use this and not patients like me or crohnology.com where I can find out about new things and also have them vetted by my friends that have similar conditions.
5. I dont think your newsletter could ever be better than condition specific newsletters like the ones from the CCFA or ADA? How will you deal with that?