Lance has been to cycling what Bobby Fischer was to chess in terms of popularity in the US. If that's any indication of the American public's attention span for activities held dear to the rest of the world but overlooked here then, yes we wil se a decline in enthusiasm for the sport. Then again, Julich and Hincapie among others seem to be carrying quite a torch for US cycling now so there may be carry over interest into other riders/ the sport in general due to that.
And hey, at least the elitists among you got to invent a cool term like "99er" to make you feel special.
NW