Rating-based discussion site for 2011: digg vs phpbb layout style?

I'm building a rating-based discussion site.

Basically, it consist in a forum were people can create topics and reply to them (and also rate them).

I have approximately 10 topic categories.

I have two layouts in mind: one is phpbb-like, the other is digg-like:

digg style:

phpbb style:

Which one is more appealing for modern users (2011)? Which one is more efficient according to UX design?