Ask HN: What's wrong with the landing page of my website?

I built an aggregator of programming stuff, which provides to every user a personalized feed of posts according to his interests. Users have the option to submit links, notes, code snippets and discuss them. The key feature is that you see only posts that are relevant to you.

It seems that the landing page has some concerns with explaining this idea.

Could you please give your feedback about it?

Website: http://tagmask.com

Thanks