Digg is set to debut a new iPhone app, according to an interview with the news site’s founder, Kevin Rose.

The revelation was somewhat unintentional: video podcasters Arnt Eriksen and Thomas Moen were interviewing Rose during the FOWA conference in London and spotted him playing with the new app. When the pair inquired about the application, Rose replied: “You’re not even supposed to know about that…nobody knows about that”. He was, however, happy for the pair to leave the revelation in their podcast. 

Separately, Digg is planning to expand to the “long tail” of content, Rose explains, serving up home pages for many different subject areas. The change could mean that Digg becomes a more reliable traffic source for publishers: currently it’s an all or nothing scenario.

Digg To Launch iPhone App [Video]

All-in-One Sidebar – this one is nice for my widescreen monitor – shifting realestate from the top to the side.

Tree Style Tabs – same as the sidebar – much more orderly now that I’m used to it and keeps the shape of my actual browsing space taller.

Xmarks – this is another must – keeps all my bookmarks synced between my laptop and desktop

TwitterBar – easy twitter posts right from the FF address bar.

Zementa – I have this but don’t really use it much. Yet.

SmarterFox – this one is actually sort of useful, but I haven’t gotten in the habit of making the most of it.

Personas for Firefox – quick way to keep Firefox looking good

Cooliris – very nice image viewer but this one is on the chopping block. Get it and use it if you like looking at pictures. A lot. And you don’t mind it being big, clunky, and not really integrated well with the browser.

Read it Later – I just began experiementing with this one. Lets you easily add links or pages to a list available for later viewing. Online or offline. List is synced with your other computers and mobile device.

Speed Dial – Every time you open a tab you see nine links with big thumbnails of your favorite sites.

That’s about it.