So-Called Town Halls

There's a traditional meaning:

A town hall meeting is an informal public meeting derived from the traditional town meetings of New England. Similarly to those meetings, everybody in a community is invited to attend, voice their opinions, and hear the responses from public figures and elected officials, although attendees rarely vote on an issue.

Then there's how politicians use the word:

President Obama has promised to change the way the government does business, but in at least one respect he is taking a page from the Bush playbook, stocking his town hall Thursday with supporters whose soft -- though far from planted -- questions provided openings to discuss his preferred message of the day.

The difference is all
in who's invited to the hall.

Seek visual variety,
to mimic normal society.

But to guarantee applause, 
enlist supporters of your cause.