It's been remade for Windows Phone 8. It currently matches Combinator's features, but I plan on adding additional features to it in the near future (such as live tiles and dynamic lock screen).
It supports multiple tile sizes.
It uses the device's theme/accent instead of the custom Hacker News theme. I may add an option to set the HN theme if people request it.
The comment view is a bit different. I think it's cleaner.
The name is different, which make it look like an "official" app. I believe people prefer to use an app named "Hacker News" than "Combinator". I'll probably drop the Combinator app in the near future.