Simple answer to the original post. Americans, (not looking to get flamed here, just pointing out a fact) admire winners. But we're hardly alone in this regard...would Mark Cavendish receive heaps of praise if he were consistently finishing 3rd? 4th? Of course he wouldn't.
VdV and Dave Z are fantastic riders. From last years Giro TTT win, all the way through VdV's Tour of Missouri win, I venture that they received the amount of "reverence" due a rider for such accomplishments. Obviously though, a TTT win doesn't single out the individual, and, the Missouri race is hardly a win that's going to secure one legendary status. Perhaps, especially given his recent solo win at Paris Nice, VdV will come to the forefront of these forums as the season continues. As for the rest? Danny Pate is solid, but so are 200 other professionals in the pro ranks. Bradley Wiggins, while also solid, doesn't win races on the road.
I won't touch the Armstrong/Landis angle, as like in politics, people's minds are set and are unlikely to change. Hamilton took a classy win at US Pro nationals last year, so obviously, the guys gonna get some press. Do US fans "revere" these guys? Some do, some don't. The same goes for fans all over the world. It's not about "pro" this or "anti" that, it's about recognizing a good performance, ie winning.
I'm from the US, but since Lemond retired, NONE of my favorite riders have been American. I just enjoy the show, and admire a classy win, whomever it may be. That being said, I'll allow for a touch of national pride to slip out for a second...I would love to see Hincapie score next month, as I can't imagine a more deserving winner of Flanders or Roubaix after so many years of close calls and bad luck.