Another idea popped in my mind: I don't know what the api and rules are, but AFAIK, an app could register itself to open, when the user opens a url with a certain prefix (for example, I think Facebook.app opens and displays iTunes' wall when you go to 'facebook://itunes' - I don't use Facebook so I don't know for sure, but I've seen other apps do this).
You can register for 'newsyc://'.
Now, when a user is on, say, 'http://news.ycombinator.com/item?id=3814563, if s/he opens a simple bookmarklet (which is a 2-line javascript code), s/he'll be redirected to 'newsyc://3814563', and magically your app would open!
I bought it just after it was announced for iPad, and used it a few times but stopped afterwards. For me, not having a chronological timeline of submissions (like 'http://www.hckrnews.com/) is a deal breaker.
Rating a comment (not a submission) is also a little hard. It takes a whole second for the controls to appear. A faster animation would be nice.
Don't get me wrong, just like the title says, it's the only iPad client that doesn't suck, and it's a great one. I recommend buying it. But it could be better.
Thanks for taking the time to create this. I know such apps usually don't generate huge revenues...
And another suggestion: use inputAccessoryView (http://stackoverflow.com/a/8998216/347353) to add a bar on top of keyboard when posting a comment (for the character asterisk, for italic text)...
You can register for 'newsyc://'.
Now, when a user is on, say, 'http://news.ycombinator.com/item?id=3814563, if s/he opens a simple bookmarklet (which is a 2-line javascript code), s/he'll be redirected to 'newsyc://3814563', and magically your app would open!