I also had a close look at the opening 24/7 a DIY Video Summit, video clip (that ironically has no poster/thumbnail/preview image as it downloads when the web page is opened). The clip a vox-pox of grabs from speakers and artists attending the event provides an insight into what to expect. Following is links to some of the organisations and people featured in the opening clip. Interesting that remixing as an approach features in many of the videos selected. In the publicity information provided in an interview with the summit co-chair Mimo Ito there is a focus on remixing:

One of the most interesting aspects of online video sharing is the fact that videos are created in an almost conversational mode, where one video is a commentary on or a response to another video, and so on. We see this kind of video and response sequence with popular remix source footage…

As part of selecting these works, curating as a practice is a feature at the summit. Links provided in the introduction video:

Anne Bray (Executive Director) - freewaves.org an alternative exhibition platform

sacha costanza chock who is involved with http://video.indymedia.org/

The Goal and Idea of the Video Network is the distribution of High Quality Videos (vhs/dvd quality) over the Internet. It is based on the Open Publishing principle of Indymedia and will allow the Publishing of Copyright Free Videos under the Creative Commons Attribution-NonCommercial-ShareAlike License.

eric saks who runs an “alternative cinema” site called flicker He says his aim with his work is to subvert “pop culture”, mainstream approaches towards audiovisual media.

Jonathan McIntosh media artist, activist who is building a website called rebellious pixels. These could be described as activist orientated re-mixes of adverts and news.

tim park doki doki productionshttp://www.doki.ca/ Anime remixes that use text to subvert the message.

laura shapiro whose thing is vidding. From wikipedia:

Vidding is the practice of creating fan-made music videos (sometimes called songvids or fanvids) that edit clips from favorite TV shows, anime series, movies, or even official music videos, to another song. It is a cross between narrative story-telling and visual poetry and their content can range from a simple tribute to a favorite character or delve into shipping/slash.

Paul Marino Thinking Machinima blog