You appear to be using identical style.css files for the wordpress and bbpress sections of your site. You can fix this by copying some CSS rules from one of my theme downloads.
I have just updated the blank bbPress themes at bbpressraw.com with new versions that have a forum-like tabular style.
You can see them in action via the theme switcher at the bottom of the bbpressraw.com forums page.
To solve your problem, I suggest you download one of the themes and copy all of the rules below:
/* Global Styles
into the bottom of your bbPress theme stylesheet. This will allow you to pick up all the bbPress CSS rules that are applied by these themes. Tweak these CSS rules in order to change the appearance of the forums.