Everyone is jumping on the bandwagon saying that the PR update is directly related to paid links. Yet, many sites that clearly do not have paid links are also suffering from a PR drop. So who's to say the message is clear?
There could be umpteen reasons why there's another update. Maybe the engineers over at Google fucked up the first time. Maybe its a plethora of reasons. Maybe there really is no update.
And since when are you so concerned about your PR anyway?