Sure, but now we have games that look pretty average being shown on the thing. I think that will do just as much damage. Hence releasing the specs will at least counter that to some degree because I generally think they're favourable. I wouldn't release specs if the 720 or PS4 was just about to come out, but they have a year on that.
Unless, y'know, they don't counter anything, exactly like last time they did it. Never mind that Sony and MS could dump vague hints of target specs right then and there to make for a pissing contest before WiiU hits market. By keeping them silent, MS and Sony have no dicks to measure against except each other's, so to speak.
As I said, misinterpretation about specs did more damage to the GameCube than "average games" ever could. Remember, this is the same console than had SMASH BROTHERS a month from launch and still crashed into 3rd place because of misconceptions about the specs coupled with the beginnings of the "kiddie" retort.