A week ago, CNN announced that it will send Floridian Jason Sauter to the hottest ticket of the year, the British Royal Wedding. Sauter -- who works as a guest service manager at Disney World and, like most citizen journalists, has no training as a reporter -- will be flown to London to cover the wedding for CNN alongside the likes of Piers Morgan and Anderson Cooper.

This is CNN’s latest step toward integrating unpaid citizen journalism with its everyday professional coverage, a key part of their success attracting an unrivaled volume of user-generated news.

Since launching in August 2006, iReport has drawn over 750,000 members from every country around the globe, dwarfing other journalism platforms that have integrated user-generated content such as NowPublic, The Huffington Post and ProPublica, which number their citizen journalists in the low thousands. MSNBC and Fox News, CNN’s broadcast competitors, have chosen to leave user-generated news almost entirely out of the equation.

iReport differentiates itself from other citizen journalism models by combining a partially undirected social media platform with a rigorous news-driven, pro-am model. CNN.com Participation Director Lila King estimates that only 50 percent of iReports are associated with a project CNN is already working on or that her team has asked for through iReport’s Assignment Desk. The other half consist of anything users believe newsworthy, ranging from a highway accident to one woman’s struggle with bulimia. By contrast, citizen journalism at other media establishments focuses almost entirely on assignment-driven content.

Britain's Prince William and his fiancee Kate Middleton pose for the media at St. James's Palace in London, Tuesday Nov. 16, 2010, after they announced their engagement. The couple are to wed in 2011. (Kirsty Wigglesworth/AP)

On Friday, the reports Sauter files from Westminster Abby will appear alongside other iReports as well as CNN’s professional coverage as part of a new user interface on CNN.com called Open Story, which launched last month at Austin’s SXSW Festival and was implemented again during the earthquake and tsunami in Japan.

Open Story places each filed piece about a single major news event on a map and along a timeline in a live, dynamic data visualization that aspires to create a coherent narrative.

If past is precedent, iReport producers will choose from hundreds of submissions during the process of curating the Royal Wedding Open Story. According to iReport, users sent in 1,291 submissions during the first 10 days that CNN covered the Japan earthquake. King suggests that this abundance of content inverts the usual process of stitching together a coherent narrative. “The editor's job becomes less pulling pieces together and more about pulling pieces out,” King says.

King describes Open Story as the “natural next step” for integrating iReports with stories filed by CNNers. “What we’re working toward here is a true collaboration among a news organization and the many people who experience an event firsthand,” writes King on the iReport blog.

Filing iReports alongside CNN-produced stories in a single aggregated narrative further weds the perceived legitimacy of each. A piece of rare exclusive footage submitted by an iReporter or a CNNer equally improves the narrative of an Open Story while a mistake by either is to the detriment of both. Having straddled this pro-am divide as the former citizen journalism editor at The Huffington Post, I’ve seen firsthand how even the prospect of such intertwining has the power to terrify professional journalists.

Legacy journalists argue that their citizen counterparts have cut in line for their 15 minutes of on-air fame or for that prized ticket to... well to the Royal Wedding. Post-"Social Network," even staunch institutionalists realize that this type of posturing comes out in a high-pitched whine.

Other detractors worry that melding user-generated news and professional journalism eschews a necessary hierarchy that should give clear preference to trained journalists. In other words, now that iReports populate CNN’s homepage, its on-air shows and even its coveted major-events coverage, some trained journalists feel they absolutely must retain some vehicle to communicate to viewers that their reports are more valuable.

This instinct sprouts from the fear harbored by professional journalism since the ascendancy of blogging. If news produced by a non-professional and a professional are given equal billing by respected media platforms, then who needs professionals? CNN is betting that both citizen journalists and paid professionals can coexist in the same space. They wouldn’t be doubling down on iReport if they believed it to be a social media sideshow unable to generate legitimate content.

User-generated reporting faces significant scrutiny when it comes to fact-checking, especially in the wake of delivery innovations like Open Story. In general, fact-checkers at iReport have a leg up on their print counterparts because submissions come with direct documentation in the form of photos and video to legitimate its claims.

While daily content normally streams in from around the globe, Open Story focuses iReport submissions on a single topic, which gives producers the additional fact checking tool of redundancy. As ProPublica’s director of distributed reporting (a term for assignment-driven citizen journalism) Amanda Michel has written, redundancy is the crucial tool wielded by pro-am editors to defend against factual error. By concentrating on a single assignment, Open Story allows iReport editors to weave together overlapping accounts of the same single facts from numerous sources.

Despite this, the Open Story for the Japanese earthquake includes a couple inaccuracies. Images of towns decimated by the tsunami show up on Open Story’s map in the middle of Japan instead of near the shore where they were captured. Of course, geomapping errors are similar in scale to the not-uncommon Chyron flubs (see this or this) that professionals across the leading news networks make regularly.

As a social media platform, iReport thrives by embracing idiosyncratic voices, which conflicts with the tempered and precise tone drilled into journalism students across the country. Johnny Colt, among the more famous iReporters as the former bassist for the Black Crowes, is unflinchingly poetic in his description of downtown Sendai after the tsunami:

“On an apocalyptic street in Sendai, Japan, I feel as if I am standing in a Cormac McCarthy novel. As though I am turning the pages, I spot a man coming out of his garage. Like a McCarthy character, the man I meet is dedicated to perseverance.”

Juxtapose that to this New York Times caption under a photo of the same area of Sendai:

“Sendai's city center, about 7 miles inland, remained largely intact after the quake, but there was massive damage along the coast.”

On the whole, iReport encourages its contributors to embrace a tone and voice that is unique and distinct from mainstream journalists, something that sets it apart from other citizen-journalism initiatives.

iReport achieved this goal while maintaining rigorous standards by allowing the vast majority of submissions, between 80 and 90 percent by my count (CNN could not provide an exact number), to remain in an online content holding tank with each piece labeled along the top in black and white, “NOT VETTED BY CNN.” Only 10 to 20 percent of submissions are certified as iReports, which then populate iReport’s homepage and can make their way onto CNN’s homepage and on-air programming.

During a phone interview, King said she believes Open Story achieves an important objective as a “way to consume a story and participate in it at the same time.” Acknowledging room for improvement she pointed out that Open Story is still in Beta.

For iReport and citizen journalism writ large, the combination of Open Story and having one of its own at the hottest news event of the season constitutes a major victory in the quiet struggle to legitimize user-generated news, or citizen journalism.

iReport continues to carve out an expanding and increasingly central part of the CNN newsroom while keeping its doors open to offbeat submissions. “Providing a space for people to tell stories that might be news is what it takes to cover the whole world,” says King.

CORRECTION: This story originally stated that Lila King was an iReport producer. Her correct title is participation director of CNN.com.