Most people love it! The ones that dont will either flock to Kiss or go canadian ! For Entercom its kind of win win for.
Actually, I know a bunch of people who are kind of disgusted by it. And they're NOT radio types either.
And I don't believe history shows a spike in ratings for Kiss as a result of this. In reality, Star & Joy listeners will not just go to Kiss (which would be the Entercom win/win as you say), but instead do what I actually do at this time of year: I change my presets to stations out of the area and/or listen to CDs for the next 5 weeks.
Ironically, as I've mentioned, many people really want to hear Christmas music between Christmas and New Years, so since Star & Joy stop on Dec 26th, many like me, probably listen to CDs for Christmas music that week.