There was another Google panda bite and algorithm update I believe on September 27. It has hurt my hub views a little bit and one of my top performing websites got sucker punched. My overall income will be down over 200 dollars this month so I feel your pain. It's gradually coming back now because I added more content and polished up what I already had.
My advice is to go in and update hubs with new information, polish them up etc. and to wait it out as best you can. Be proactive, but don't panic because these things happen and I suspect this hit a lot of hubbers because numerous people have posted frustrations. HubPages itself perhaps took a pounding in that update.
Hang in there - and as the saying goes, don't put all your eggs in one basket. The beauty of diversity is that when Google has a tantrum - I mean update, you don't lose everything if you are publishing in more than one location.