Also interesting to note was that this trend goes both ways: when blood elves debuted, the males were much closer to the females and were beefed up in The Burning Crusade beta. As Annalee Newitz pointed out, the other race that debuted in BC, the draenei, are extremely dimorphic; males are bigger and more massively muscular than orcs, while their females are far less mesomorphic. What interested me, at least so far as the tauren and troll model changes went, is that players complained that the tauren and troll women weren't to their liking, which most likely had an influence on the design of draenei and blood elves.
Now, with Cataclysm, we have two new races to consider. How do the worgen and goblins stack up on the dimorphism scale?
Well, goblins may well be the least dimorphic race in WoW, or at least a contender. (Gnomes aren't terribly dimorphic either, so it may be as simple as a consequence of geometry.) Male and female goblins certainly are distinct from one another in their playable incarnation, with males having slightly more pronounced features and females being slightly taller.
How, therefore, did our Gilnean friends come out of their curse? Well, since worgen were once human, we're already talking about a fairly dimorphic race in WoW. All human males, from the mightiest warrior to the warlock and wizard, are built like brick outhouses, as my father used to say. (He didn't say "outhouse," but you can understand why I made the substitution.) But do worgen maintain the dimorphism of their parent race?
I wouldn't say so. It's not that they maintain it -- it's that they take it as a foundation and go wild with it. One of the interesting aspects of World of Warcraft is that many of the males crouch; worgen are no exception to this trend, although they're the first Alliance race to do so. Orcs, tauren, trolls and now goblins all have between a slight and severe crouch or hunch to their posture in the males. Tauren females are taller than tauren males unless you count the pronounced hump on the male's backs; the troll females stand generally taller than the males, save for the rare moments when the males straighten all the way from their extremely severe crouching posture. Worgen are similar in this regard.
Why the worgen curse makes women grow taller than men, I have no idea, but there it is. It's also interesting that while the female is taller, every aspect of the male from the head and jaws to the hands and feet grows massively, while females see very little in the way of growth of those portions of their anatomy. The worgen male sports a massive maw of savage fangs, while the female's mouth (although still a large muzzle full of sharp teeth) is far less developed, almost fox-like. Much like the tauren or draenei, the worgen male is nearly double the width of the female.
Interesting that of our two new races, the goblins come off as nearly physically equivalent between genders, while worgen exaggerate the already striking dimorphism of their parent race -- especially considering that most Gilnean women you meet in the game are such astonishingly aggressive and forthright women.