I think lalumia brings up a great point that some of you may not be aware of.
And Clubber, +1 on both of your posts bro.
I guess some Top 40 fans in New York don't always realize just how good Z-100 is when compared to most CHRs. Don't get me wrong, there's some other great/well programmed CHRs across the country, but Z-100 is in some ways in a league of its own.
Chicago's 103.5 Kiss FM has been in a state of war with Chicago's heritage Rhythmic, B-96, for years now. As a result, Kiss FM which is supposed to be the market's CHR/Pop station oftentimes sounds like a Rhythmic. Conversely, B-96 leans CHR/Pop for a Rhythmic station, at times more mainstream sounding then Kiss. B-96 is actually much more supportive of "Love Song" by Sara Bareilles then Kiss, and played some Daughtry records when Kiss didn't. Oh yeah, and neither station has shown its been able to dominate in the ratings the same way Z-100 does.