Just noticed it a couple days ago. Seems to do it across multiple platforms.
The bubble icon next to the posts and forums to indicate that there are or are not new posts (White, or Greyed Out) seems to not be working correctly. Sometimes showing new posts when there are none, sometimes showing no new posts when there are some.
Firefox 34.0 (Windows 7)
Safari on iPhone 5S iOS 8.1.1
I don't really see a pattern to it.
Edited, Dec 4th 2014 10:57pm by TirithRR