Not really sure if this was posted already, so sorry if it was.
I have seen this before it only seems to happen sometimes and in some categories, not sure if it was only bug category I seen it before but It seems anyway posts I guess in that thread there name goes red on the index page while if you actually check they are still just members.
<img src="http://screensnapr.com/e/FxspfC.jpg" border="0" />
Using chrome, it's a small bug but just thought I'll mention.