That's exactly what I'm planning to build! I'm not sure if I should go hybrid or all-in.
By hybrid I mean that people could receive regular human-readable emails, but senders could include a small url or tag that links to the semantic information (it could be an event invitation, receipt, valid email confirmation, password changing, task proposal, marketing offer, flight information, etc.).
The "smart" email client could then automatically interpret semantic emails, and act accordingly. It would also hide those emails, and only show you the relevant notification.
Unless you plan to discover new ideas by mistake, you absolutely need a vision, and then find the way to get there.
If you start from the bottom (bottom-up), you'll constantly compromise technically, as lots of things are not yet possible to do.
If you start from the top (top-down), you'll "know" that it's possible to accomplish, and you'll only have to find out how to do it.
You have far more chance to solve an enigma if you know there is an answer than if you don't. Visionary ideas make you believe the answer exists, which makes it much more easier to accomplish.
I don't know what your product is or does, but from what I just read, it doesn't seem to be very innovative.
You're building a faster horse instead of a car.
The solution lays in semantic communication. As long as you mainly communicate with text that someone has to read, analyze and understand, you're doing it wrong.
The problem with emails is not the spam or the sorting, it's that they're not actionable. Tasks in a to-do list are almost directly actionable, and that's what most emails aim for.
To be honest, I think I prefer your app to my app :P Just move the about section somewhere else (and link to it from the application bar menu). You should also sync the details animations.
Where do you get your data from? Do you use data scraping?
For the moment, you can read posts using iHackerNews (that's the quick solution I came out with). I'm working on native comments but it will take some time (don't expect it this month, I'm too busy).
http://ihackernews.com/ is an excellent Hacker News mobile website. It also provides the third-party Hacker News API used by Combinator.
The problem is that Windows Phone doesn't allow users to pin website icons to their start screen (you can pin a static web page preview but it doesn't look very good). Fortunately, http://www.web2tile.com solves this issue, but not enough people are aware it exists. I may try to build a native app for it, but I'm not sure Microsoft would allow it.
I just released my Hacker News reader app on the Windows Phone marketplace, and saw your post while I was testing mine. Why are so many people developing Hacker News app all of a sudden?
It just looks awful.