Lack of interest Keyboard Shortcut

Can you please implement a simple keyboard shortcut system? Basically, the only function I want is being about to use arrow keys to read through a long thread: up and down to navigate in-page while left and right to go to the next or previous page. That would be awesome!

You can always make it more appealing by using an overlay with available shortcuts for each page. Something similar to Gmail's "SHIFT+/" for example. Anyway, this can be done quite easy with jQuery as a addon later but I think it would be nice to have shortcut as a built in feature.

Thank you