The new design of the site has been put into place. There are currently three options to choose from. The default "Dark" style, featuring white text on black...based off the former default style. The second style is the "Light" style. Same as the dark, but in reverse, black text on white. Finally, the Blue style (one of the original styles of JO) is being kept around for nostalgia.

There are two ways to choose which style you view on the forum.
The first: if you scroll to the bottom of any page of the forum, there is a drop down menu labeled "Select A Forum Style Here:", use that to choose a style.

The second: Go into the UserCP, click on Edit Options. At the very bottom of this page is a section labeled "Forum Skin". There you can also select the forum skin for your account.