So, I've been pondering these distinctions:
group
community
group-that-becomes-community
"natural" group
organization (coalition, alliance, network, thinktank)
public
counterpublic
Here's my question, isn't a public just a very large group? A public is constituted how? by virtue of being an audience? because they engage in the same behavior (such as voting)? because they have a shared/common goal (elect a certain person)? what makes a public so special?

In the most recent election, we saw first-hand the agenda setting function of the media, wherein it didn't tell us what to think but it certainly told us what to think about, by repeating endlessly the talking points of the conservatives and Republicans.
As I understand it, a public (or perhaps an audience)has shared beliefs and experiences. These shared beliefs and experiences may cohere around a charismatic leader or around a cause. One of my red-state friends keeps sending me these bizarre e-mails (well they aren't bizarre to her, but I cannot imagine how any sane person could see the world this way) about how G-d has blessed President Bush and the election was proof that Americans support his Christian values. Now, Americans may support a lot of things, but saying that Bush *represents* "Christian values" is something I can't wrap my mind around. Yet all of the people in her church and in her community share this view. She homeschooled her kids, and the bible college she sent them to framed Bush in this way as well. SO, is my friend part of a public? Absolutely. And she, along with other members of this public, seek out only information that reinforces their beliefs, as well as evidence that demeans those who disagree with her.
The downside is a public can turn into a mob very easily, as Hitler, Stalin and others can attest. Nothing like a bunch of "true believers" with a mission to purify the world of "evil" (there goes poor Professor Levinas, spinning in his grave again-- we don't wanna know the other, since we believe he or she is evil...)
But on its good days, a public, especially an enlightened public, can demonstrate in the streets and bring about social change, fight for civil rights, stand up against tyranny. Or it can just give up and remain apathetic and uninvolved. Or it can get motivated and join with other like-minded individuals who are all convinced that things need to change. The problem for us is how to bring about some exchange of ideas between these various publics, especially the ones who believe their religion gives them the right to do whatever they want to those who disagree...
In terms of some important readings, I trust you will comb through Dewey, Hannah Arendt, and Habermas (esp. Structural Transformation and Between Facts and Norms), and the Hauser book on our syllabus. The other significant read here is Michael Walzerís 2002 essay ìPublic and Counterpublicsî (Public Culture 14/1) and his book by the same name. Therein he distinguishes between three kinds of publics: (1) a bounded public, which is what I understand you to mean by ìgroup;î (2) THE public, which is a social totality akin to the demos; (3) A public, which is constituted through texts and performances. My lament about your emphasis on groups has always been that you hit (1) but not usually (2) and rarely (3). My critique concerned what I see as a psychologizing of ìgroupsî and group activity that prevented you from embracing (2) and (3), which lie more in the domain of rhetoric. You could consider this the micro-macro level problem, but as I said long ago, sometimes the benefits of hitting both do not outweigh the benefits of looking at one in isolation. Here is such a case. Much can be learned of the ìmacro-levelî of the / a public without having to take recourse in a bounded audience. One can profitably engage all three, of course, but I think what might be holding you up is an insistence that the micro and macro must relate to one another. (Incidentally, Beckyís contributions to our discussion also have a micro-macro level, but I think she more directly gets to the other aspects of the / a public, perhaps because she is more attune to the rhetorical than the psychological.)
For further information on the rhetorical approach to the / a public, check out:
Robert Asen and David Browner, eds. Counterpublics and the State. 2001.
John Lucaites and Robert Hariman. ìPerforming Civic Identity.î QJS 88 (2002): 363-392.
Carole Blair. ìParables from Public Places.î WJC 65 (2001): 271-295.
Gerard Hauser and Carole Blair. ìRhetorical Antecedents to the Public.î Pre/Text 3 (1987): 139-167.
Hans Hohmann. ìRhetoric in the Public Sphere.î QJS 84 (1998): 358-393.
Jay Rosen. ìMaking Things More Public.î CSMC 11 (1994): 363-388.
Happy Festivus to all, Stephen
I would second Donnaís notion of the political constitution and competition between multiple publics. There again lies a question Iíve had with your emphasis on groups, Steph, namely the role of the political. Yes, I understand that everything is political so groups are therefore political, but Donnaís point that we take the / a public as a site for overt political action and judgment is important. I do think you can profitably relate the work of groups to the work of a public, and I might also go so far as to think that work of groups can lead to the changes of ideology and practice among publics that Donna seeks (and thus opens up space for grassroots activism). But I would caution against locating too much power within group activity, when indeed the constitution of a / the public is the heart of political rhetoric, and is accomplished through other means not bound to group activity, such as media displays, political speeches, political coordination of public rituals, etc. That is, group work is no substitute for public work, although they certainly do relate.