What idioms describe something that's really popular and is being fought-over by many different people?
"the latest bone of contention" - the latest topic about which people are arguing. The metaphor here is of two dogs fighting for the same bone. I added "latest" to get to your intended meaning of "popular", but I'll have to think of more related expressions.
You could also be like most journalists and overload the poor word "controversy" with all kinds of connotations related to popularity :)