Thanks for the links Michael and Amanda, this is an enormous, enormous topic! Thanks for bringing it up. Just a quick point: if you're writing this up for a paper, I would be careful to distinguish "Web 2.0" and online video as separate categories. It seems like you're collapsing them into the same thing here.
I second Michael suggestion that you go through Rhizome's blog to find artists working in online video - there are quite a few.
Rhizome's been heavily involved with this area for some time, in terms of Rhizome-specific resources related to online video and web 2.0, I would consult:
Rhizome Artbase (searching for works tagged "video"):
http://rhizome.org/art/Montage: Unmonumental Online
http://rhizome.org/art/exhibition/montage/Montage: Unmonumental Online Panel, videos available through Rhizome's Vimeo
http://vimeo.com/2113217Net Aesthetics 2.0 Panel, videos available through Rhizome's Vimeo
http://vimeo.com/2183401Ed Halter, After the Amateur: Notes
http://rhizome.org/editorial/2566Greg J. Smith Out of Context: Artists and Web Inventories
http://rhizome.org/editorial/2279Carolyn Kane Dancing Machines: An Interview with Natalie Bookchin
http://rhizome.org/editorial/2653Jonah Brucker-Cohen Report from Ars Electronica 2008: A New Cultural Economy
http://rhizome.org/editorial/20Rick Silva, Interview with Mark America
http://rhizome.org/editorial/3080Resources relevant to the role of video in the atmosphere of the internet - copyright issues, circulation, history of bootlegging, etc:
Sven Lutticken Viewing Copies: On the Mobility of Moving Images
http://www.e-flux.com/journal/view/75Oliver Laric, Versions, 2009
http://oliverlaric.com/versions.htmIn Defense of the Poor Image by Hito Steyerl
http://www.e-flux.com/journal/view/94Dara Birnbaum and Cory Arcangel: In Conversation from Artforum, March 2009
Lucas Hilderbrand's Inherent Vice
http://www.amazon.com/Inherent-Vice-Histories-Videotape-Copyright/dp/0822343762Ed Halter's Television for the People
http://www.canopycanopycanopy.com/5/television_for_the_peopleOpen Video Conference in 2009
http://openvideoalliance.org/open-video-conference/Marisa Olson Lost Not Found: The Circulation of Images in Digital Visual Culture
http://www.wordswithoutpictures.org/main.html?id=276Resources relevant to the history of cinema, video & the online environment:
Sean Cubitt's The Cinema Effect
http://mitpress.mit.edu/catalog/item/default.asp?ttype=2&tid=10722Yvonee Spielmann Video: the Reflexive Medium
http://mitpress.mit.edu/catalog/item/default.asp?ttype=2&tid=11338Mary Ann Doane The Emergence of Cinematic Time (esp. the chapter The Instant and the Archive)
http://www.hup.harvard.edu/catalog/DOAEME.htmlAnne Friedberg The Virtual Window
http://mitpress.mit.edu/catalog/item/default.asp?ttype=2&tid=10780Lev Manovich The Language of New Media (esp. the chapter What is Cinema?)
http://mitpress.mit.edu/catalog/item/default.asp?tid=8830&ttype=2