I don't know this means the ban on scantily-clad booth babes at the Penny Arcade Expos necessarily gets any stricter, but the policy - put to a poll of Penny Arcade's community last week - is definitely getting more descriptive.
The biggest inclusion the PAX community wanted to see in the policy is that a booth rep "needs to be trained/educated about the product." So if that's applied to everyone in the booth, cosplaying or not, it'll probably cut down on eye candy since, as we see in ads for E3 booth babe gigs, it's not a job marketers want to pay any money or spend much time training someone to do
Eighty-one percent of respondents to their poll wanted booth reps who knew something about the product. So if that condition has primacy, then the semiconflicted language about what kind of dress is and isn't allowed may be a moot point. "Anything that is considered "partial nudity" is banned." OK, pretty definitive. Also, "No messaging that specifically calls out body parts," will be a part of the policy. That said, "cosplayed characters are allowed to wear revealing outfits, assuming it is true to the source game."
It's cool of Penny Arcade to include its community's wishes on this, and certainly its policy is its own business. Nitpicking what conditions have primacy is kind of a pointless argument, though. Like I said, I don't know that the no-booth babe ban got any more or less strict, but the language and the reasoning behind it is at least more articulate.
PAX Booth Babe Survey Results [Penny Arcade Forums, thanks ACC3SS]