If you want to use it like it used to be nothing has changed! The only thing is that the forum list is gone. However, this forum list is now in the top of page navigation bar. So you can jump to any forum from any page if that's your wish.
The first bar should have All (which is default). Now click on the "forum" you want (like Deals, Vouchers, FS/FT etc). Click on "text only" in the View Options if you want forum style layout. Use the hot, new and discussed tabs to order the posts how you want.