talking point

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A position or planned series of remarks on an issue or an aspect of an issue, especially when used to help guide a person's discourse in public and in the media.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A specific topic raised in a conversation or argument which is intended as a basis for further discussion, especially one which represents a point of view.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun an especially persuasive point helping to support an argument or discussion