Ok, so it has been discussed on more than one blog. It is interesting how this is filtered through so many different views! The funny thing is the mudflap girl is just a bumper sticker you can get. It is not the general billboard type advertising the general public will see.
So, if you put it into the context of bumper sticker it makes more sense. Yes, I do see it as sexist though. I have driven behind too many mudflaps on the highways of MT not to be offended in some manner.