How many wins did Lance Armstrong have before John Q. American knew who he was? Even with Armstrong's back story of being a cancer survivor, it was only after two or three wins that the average non-cycling American paid attention to Le Tour.
So if VV wins this year, I'm sure it will make the news and a year from now a few more people will recognize the name and maybe even watch some of the TdF 2009. Will the TV ratings change? No. Will the Giro d'Italia be on Versus every morning? No.
Sad to say, but Landis will still be a more recognizable name.