I thought I'd post this here since we'll all be seeing it soon.
 
Karen, If your ferret is healthy, happy, eating well, ect..., then what we
have here is a case of seasonal weight lose.  If I remeber correctly, he's
young, so maybe you've never seen his summer weight before.  Ferrets tend
to lose a lot of weight in the summer, and, correct me if I'm wrong, males
lose lots more than females.  So rest easy and just keep an eye on the
little bugger.
 
I noticed just yesterday that mine are becoming slimmer.
 
Holly and Five Frolicking Ferrets
TJ (Love my harem)
Rascal (I will dig carpet, I will dig the plants, I will....DIG!)
Samantha (Where's Snow, I wanna CHOMP! her!)
Maggie (I don't like other ferrets, stay away from me.)
Snow (Quit Chomping, that hurts!!)
[Posted in FML issue 1878]