56. A machine system structured to automatically present as first presentations to a first user thereof, immediately acceptable invitations to join in on system-identified telecommunications-mediated information exchange forums based on automatically repeated determinations by the machine system of recent focused-attention activities of the first user on specific subsections of content made available to the first user by way of a user-accessible content presentation device, wherein the automatically repeated determinations regarding recent focused-attention activities are carried out transparently by the machine system without need for diverted focusing of attention by the user directed to aiding the repeated determinations automatically carried out by the machine system, and wherein: the first presentations are automatically presented in an invitations clustering area of a display viewable by the first user; and the first presentations, which are automatically presented in the invitations clustering area, can include immediately acceptable invitations to two or more different and system-identified kinds of telecommunications-mediated information exchange forums, the different kinds of information exchange forums each being one that has at least one other user co-invited to it or already participating in the forum and the presented different kinds of information exchange forums including two or more of: an open-to-the-public chat room; a private chat room; a restricted access blog; a peer-to-peer forum; a forum that sends emails to a predetermined one or more listed recipients; a twitter exchange; a live video conference; a live video web conference; a live voice only conference; a multi-cast-provided cross-exchange of relatively current informational content; a network-provided cross-exchange of relatively current informational content; a broadcast-provided cross-exchange of relatively current informational content; a chat room which is spawned by the machine system; a moderated online exchange service, or different forums which are respectively directed to different topics; different forums which are respectively logically linked with different ones of respective content elsewhere presented to the first user; pre-existing forums to which the first user was invited at different times; different forums whose respective participants are geographically clustered in respective different geographic areas; different forums which restrict their participant population to different ones of predetermined number of minimum and/or maximum simultaneous participants; different forums which restrict all or a pre-specified portion of their respective participant population to participants to different and respective variations of the participants having at least one of: specified credentials in a specific topic; specified minimum or maximum levels of education; specified proficiencies in specific topic areas; a specified mix of demographic attributes within the forum such as the forum's participants defining a specified mix of credentials in a specific topic, a specified mix of participant ages, participant genders, participant socioeconomic classes, participant political party affiliations; a validated set of one or more demographic attributes such as age, gender, socioeconomic class, education level, place of residence; a specified level of sophistication in a specific topic area; and a specified leaning in favor of, against, or undecided with respect to a specified proposition; wherein at least a portion of the machine system includes a data processing machine; and wherein said automatically determined and recent focused-attention activities of the first user occurred no more than at least one of: 3 hours prior to said presentation of the first presentations to the first user; and a determined time duration prior to said presentation of the first presentations to the first user, the determined time duration being determined based on a currently active profile characterizing the first user.
56. A machine system structured to automatically present as first presentations to a first user thereof, immediately acceptable invitations to join in on system-identified telecommunications-mediated information exchange forums based on automatically repeated determinations by the machine system of recent focused-attention activities of the first user on specific subsections of content made available to the first user by way of a user-accessible content presentation device, wherein the automatically repeated determinations regarding recent focused-attention activities are carried out transparently by the machine system without need for diverted focusing of attention by the user directed to aiding the repeated determinations automatically carried out by the machine system, and wherein: the first presentations are automatically presented in an invitations clustering area of a display viewable by the first user; and the first presentations, which are automatically presented in the invitations clustering area, can include immediately acceptable invitations to two or more different and system-identified kinds of telecommunications-mediated information exchange forums, the different kinds of information exchange forums each being one that has at least one other user co-invited to it or already participating in the forum and the presented different kinds of information exchange forums including two or more of: an open-to-the-public chat room; a private chat room; a restricted access blog; a peer-to-peer forum; a forum that sends emails to a predetermined one or more listed recipients; a twitter exchange; a live video conference; a live video web conference; a live voice only conference; a multi-cast-provided cross-exchange of relatively current informational content; a network-provided cross-exchange of relatively current informational content; a broadcast-provided cross-exchange of relatively current informational content; a chat room which is spawned by the machine system; a moderated online exchange service, or different forums which are respectively directed to different topics; different forums which are respectively logically linked with different ones of respective content elsewhere presented to the first user; pre-existing forums to which the first user was invited at different times; different forums whose respective participants are geographically clustered in respective different geographic areas; different forums which restrict their participant population to different ones of predetermined number of minimum and/or maximum simultaneous participants; different forums which restrict all or a pre-specified portion of their respective participant population to participants to different and respective variations of the participants having at least one of: specified credentials in a specific topic; specified minimum or maximum levels of education; specified proficiencies in specific topic areas; a specified mix of demographic attributes within the forum such as the forum's participants defining a specified mix of credentials in a specific topic, a specified mix of participant ages, participant genders, participant socioeconomic classes, participant political party affiliations; a validated set of one or more demographic attributes such as age, gender, socioeconomic class, education level, place of residence; a specified level of sophistication in a specific topic area; and a specified leaning in favor of, against, or undecided with respect to a specified proposition; wherein at least a portion of the machine system includes a data processing machine; and wherein said automatically determined and recent focused-attention activities of the first user occurred no more than at least one of: 3 hours prior to said presentation of the first presentations to the first user; and a determined time duration prior to said presentation of the first presentations to the first user, the determined time duration being determined based on a currently active profile characterizing the first user. 57. The machine system of claim 56 wherein the invitations clustering area includes at least one of: a side banner disposed at a side of displayed window or of a screen viewable by the first user; a top banner disposed at a top of displayed window or of a screen viewable by the first user; a pop-out radar scope-like area; a scrolling marquee; a pop-out menu bar that pops out from a screen edge; a shrinkable or hideable banner that correspondingly shrinks to or hides along a window edge; a distributed plurality of banners distributed in windows and/or in a main area of a screen viewable by the first user; a banner that has invitation-representing icons scrolling therein; and a collection invitation representing icons and/or other glyphs.