I have been steady at 49,500 for almost eternety is seems, now all of a sudden I a fluctuating from there to 20,000 and it will change almost constantly everytime I validate. My PR hasnt changed, the only think I have noticed with my backlinks is that my domain without the www has dropped to 0 backlinks and no PR, and my domain name with the www has doubled in backlinks with PR remaining at 4 where it has been for a long time.
Google treats www.example.com and example.com as unique. If you example.com has dropped then you need to change you prefrences in the co-op to www.example.com and revalidate. Then you should be up and rolling.