Holy Shit Tasty, you stole my thread! I kid you not, I was just about to do a write up like this, but I didn't have the time. So, I guess congratulations, you dirty, dirty thief.
In regards to your/my thread, I would like to point out something interesting I heard in a promo, when Batista was in qthe quest for World Heavyweight Gold, with Rey Mysterio and Taker standing in his way latye last year. In the video package, he says: "Everything about me screams World Heavyweight Champion". And you know what? He is absolutely right. You cannot deny that when you see Batista, you are in awe. But it's not just that. It's the trunks, the boots, the music, the pyro, the walk down the ramp. Everything about him tells you that he is the man who will be World Heavyweight Champion. Batista has the look, and regardless of whether you like him or you don't, Vince McMahon obviously thinks he has the look as well.
But can we quantify "the look" so easily? Do all successful wrestlers have to be 6'6 and 300 pounds? Perhaps if we take a page out of the golden age of wrestling this would seem to be the case. Hogan certainly left his mark on the world of wrestling, and he is no small man. Then he dropped his first Mania loss and the biggest rub possible to the Ultimate Warrior, yet another genetically gifted muscle bound wrestler. Even your favourite Tasty, Randy Savage who was billed 6'2, 237 pounds, didn't look like a slouch at all. I think that this era defined what many people thought and still think is the look. Everyone wishes to attain the near god-like popularity of Hogan, and thus follow him in this vein. NorCal supports this wholeheartedly I guess.
I think then, that the New Generation introduced fans into the new build and look of wrestlers. Bret Hart and Shawn Michaels weren't the biggest guys in the business. They were always played as the underdogs, Shawn Michaels against Vader, Bret Hart vs The Undertaker. Their builds fit in perfectly with their gimmicks, and changed our opinions of what we thought was the blueprint for the World Champion. When they tried to push Hulk Hogan v2.0 in Lex Luger, Bret Hart was chosen over him, proving that being muscled didn't always grant you the success you wanted anymore. Of course, you still had big guys who did very well for themselves such as Diesel and Taker, but the smaller guys weren't being relegated all of a sudden to wimps who could never touch the WWF title. Then again, this was the worst period in WWF history numbers wise, so take into consideration.
The Attitude Era was interesting, in that I think the look became less important. Stone Cold and The Rock were megastars, and would have been no matter what they looked like, as their charisma and talent far exceeded simply their builds. People didn't care that Mankind was tubby and was missing some teeth and ear. People willingly enjoyed watching a skinny Kurt Angle as much as they liked seeing a ripped HHH. This era was a true melting pot of perspectives and idea, as peoples opinions changed so much due to the sheer quality of the product.
You still have remnants of wrestlers from all categories around today though. We still have mixing of "looks", and no one can be said to "define" the era. Batista and Triple H exemplify the "Golden Age" look, Chris Jericho and John Morrison could be lumped into "New Generation". Perhaps we're seeing a new category "The Filthy Indy Wrestlers from down the road" in Daniel Bryan and CM Punk, who knows.
But a good thread and an interesting topic that I think ultimately falls down to personal opinion. When were you a kid, when did you watch wrestling and who did you idolize? The look all depends on what you like to see, but the talent of wrestlers will always surpass "the look" in terms of importance. See: Bobby Lashley.