New York Times Reader
Found this yesterday: the New York Times has developed a reader application based on Microsoft's WPF api. Take a look here
Some sources on the internet claim it uses xps technology; I tested the applications, but I'm not 100% sure about this. The content that comes from the server might be in xps format, but as you cannot see what really goes on, one should need to sniff the internet connection to really find out.
What it does show is that apparently the NYT felt that 'the browser' as 'content delivery tool' was lacking. Interesting.