This is a preliminary screenshot of 2.0 running on Ubuntu Linux 7.04. The two big white square that you can see are both tree controls (like the bit on the left hand side of explorer. The idea is that you'll select the directory you want and it'll appear in the tree control, selecting preview (which will be on the toolbar) will the score through the files that will be removed from each directory and add new files in italics, allowing you to see what effects the blacklist will have and exactly what will happen.
This screenshot shows the new blacklist pane, as you can see it will give you many more options than the old exclusions list. Although it doesn't say on that picture you will also be able to exclude files by date modified and size.