Word for an idea that quickly comes to dominate discourse on a particular issue?

I'm looking for a word that describes an idea that captures people's attention and quickly eclipses discussions of other ideas related to a particular issue. Incendiary is almost the word, but without the suggestion of inflammatory content.

Thank you!

Solution 1:

hot-button

: an emotional and usually controversial issue or concern that triggers immediate intense reaction

"Hot Button." Merriam-Webster.com. Merriam-Webster, n.d. Web. 26 Apr. 2016.

burning issue or question

3: of fundamental importance : urgent < one of the burning issues of our time>

"Burning." Merriam-Webster.com. Merriam-Webster, n.d. Web. 26 Apr. 2016.