The class role forums have closed their doors. Takralus posted on them yesterday that they're doing so to concentrate the discussion into existing forums (which I'm taking to mean the class forums). The role forums are currently in read-only mode, and will remain that way until April 8, when they are removed entirely.
The role forums were launched in October 2008 with the original intent of replacing the class forums. Blizzard backtracked on that quickly after the player base revolted, and they left everything in place as it is today. Ghostcrawler was a big poster on the role forums and used them extensively before he made his switch to Twitter. However, as we all know, the forums were not always a happy place.
Takralus' full announcement after the break.
Update 3:22 p.m.: Bashiok let us know that this only applies to the EU. They have no intention of closing the US class role forums at this time.