2ND UPDATE: A 5 AM walkthrough of the Royal Wedding route took place today complete with carriages, trumpeters and up to 1,000 members of the Armed Forces wearing full ceremonial uniform. Meanwhile, the first spectator has claimed his spot right outside Westminster Abbey, kitted out with flags, a sleeping bag and an umbrella. But when Prince William slides the wedding ring on Kate Middleton’s finger on April 29, will there really be an expected global audience of 2 billion watching? NBC keeps saying “it’s completely false” that it has cut back on the number of pre-taped segments because U.S. networks may have overestimated America’s appetite for all things House of Windsor compared to 1981, when William’s father Prince Charles wed Lady Diana Spencer. This time, around 140 million U.S. viewers are expected to watch. Worldwide, when 800 million watched the Charles-Di nuptials, this time Tim Santhouse, operational manager at AP Television News Global Media Services tells me “the volume of broadcasters coming to London, and the number of camera set-ups involved, is unprecedented in terms of interest from overseas broadcasters and the proliferation of news outlets.” AP will be providing camera set-ups and satellite uplinks for around 60 networks doing direct-to-camera pieces including Canada’s CTV, Australia’s Channel 9, and Arab news channel Al-Jazeera. The 62 broadcaster members of the European Broadcast Union -– which include ARD in Germany, France 2 and RAI in Italy –- will be getting their clean feed directly from the BBC. Sam Dubberly, who is in charge of forwarding BBC coverage, tells me, “the closer we get to the wedding, the more requests we’ve been getting from members.” But NHK, the Japanese state broadcaster, won’t only out of respect for its still-grieving population in the wake of the earthquake/tsunami disaster.

Talk about a high-tech event: one estimate has 8,000 TV and radio reporters and support staff traveling from around the world into London to cover the nuptials, which start at 3 AM PT. Around 140 outside broadcast trucks with satellite uplinks will be parked in nearby Green Park, with every major world broadcaster lining up cameras along the procession route. The BBC will be using 21 cameras inside the scene of the wedding itself, Westminster Abbey, some of them wireless and remote-controlled. But Prince Charles’ office stopped Rupert Murdoch from shooting the wedding in 3D, saying there just wasn’t enough room for his extra equipment in the Abbey.

Here’s who’s trying to cash in on Friday’s wedding day:

BBC: The BBC is hosting the TV coverage and pooling it for U.S. networks, but stresses that it is not making any profit out of the wedding. But how much broadcasters are being charged and where the money is going is being kept under wraps. The Beeb alone is sending 850 staff to cover the wedding. The Beeb’s critics say that once again the UK state broadcaster is just throwing public money at the event. Huw Edwards, the Beeb’s evening news anchor, will be leading BBC1’s coverage throughout the day. The channel’s feed will be made available to BBC Entertainment viewers across Asia, India, Latin America, Europe and the Middle East. BBC1 will be also broadcast on BBC Knowledge in Africa. There will also be a slew of royal docs on BBC Worldwide channels, including one about William and Kate’s relationship from their first meeting at St. Andrew’s University in Scotland to the present day. The BBC, meanwhile, has married The X Factor to the Royal Wedding to the delight of UK tabloids by hiring an assistant stage manager to help with its TV coverage.

NBC/ITN/ITV: NBC News has partnered with ITN for its royal wedding coverage. NBC will base 50 staff at the central London production base of ITN, the news arm of ITV which is co-producing NBC’s coverage. The U.S. broadcaster will offer 20 hours of combined coverage with MSNBC on the wedding day. Matt Lauer and Meredith Vieira will present a one-hour primetime doc tonight (8pm/ET) , while Martin Bashir –- the Brit reporter who famously got Princess Diana to admit Prince Charles’ adultery on TV –- will lead MSNBC’s London coverage. Every NBC brand will be devoting coverage to the event including live coverage on Today, Access Hollywood, Bravo, E!, Telemundo, The Weather Channel and women’s website iVillage, which will feature “an exclusive interview with the couple’s former landlady”. The UK’s biggest private network channel will have 10 hours of live coverage on April 29 from 300 ITV staff. There’ll be extended news peak-time news programmes, including an hour-long early evening news special at 6pm (1pm ET), plus an extended edition of its flagship ITV News at Ten. Its main anchors will be news presenter Julie Etchingham and daytime host Philip Schofield. ITN is charging broadcasters up to £200,000 ($327,310) each to access a “clean” feed of the build-up and ceremony so channels can then overlay their own graphics and commentary. ITN charged $2,350 for each minute of Prince William’s and Kate’s engagement interview last November, with proceeds going to Prince William’s and Prince Harry’s charitable foundation. ITN is set to have its own Royal Wedding payday after hiring out its facilities to more than 100 staff from 15 international broadcasters, including Canada’s CTV, Germany’s ZDF and Australia’s 7 Network and Network 10.

FOX/Sky: Fox News is not paying for its feed because Sky News is already one of the 3 official UK networks covering the event. Fox News is shipping in at least 50 staff from American offices. Shepard Smith and Martha MacCallum will anchor live coverage of the wedding beginning at 1 AM PT. The network’s programming leading up to the event will include the documentary Countdown to the Royal Wedding (April 24) and simulcasts of the UK’s Sky News (April 27th-28th). Eamonn Holmes, Sky News’ breakfast anchor, will be leading rolling coverage on the Sky News channel from 160 staff. Sky News’ coverage will begin at 6 AM (10 PM PT Thursday) on the day from a purpose-built studio outside Buckingham Palace. Holmes will be joined by Sky’s royal correspondent, Sarah Hughes. There will also be reporters on hand in spots around Britain significant to the couple, including St. Andrews in Scotland, where they met; the Welsh island of Anglesey, where they now live; and Kate Middleton’s home village of Bucklebury. Sky Living, Sky’s female-skewing channel, will be airing a cheeky tie-in, How To Nab a Prince, presented by actress Patsy Kensit.

CNN: CNN already has 75 staff in its London bureau. But Piers Morgan will be the linchpin of the network’s coverage, believing that his British accent and London connections will give him the edge over rival presenters. Morgan, who has photos of himself snapped with the royals dotted around his house, boasts: “I’ve met and know quite well most of the royal family. I have connections that most American anchors can only dream off.”

ABC: Diane Sawyer and Barbara Walters will anchor ABC’s live coverage of the wedding of beginning at 1 AM PT on April 29, followed by a live West Coast edition of Good Morning America hosted by Robin Roberts live from Westminster Abbey. The wedding caps a bunch of Royal Wedding programming on the network, beginning April 18 with a Special Edition of 20/20: William & Catherine: A Modern Fairytale, anchored by Walters. Throughout the week leading up to the event, GMA, World News With Diane Sawyer, Nightline and 20/20 will broadcast from London.

CBS: Outgoing CBS Evening News anchor and former Today star Katie Couric will lead live coverage of the event. Couric will also anchor a one-hour primetime special at 8 PM that night, airing against NBC’s special hosted by Matt Lauer and Meredith Vieira.

Channel 4: The 4th UK broadcaster, which specialises in youth programming and the irreverent, will just be extending its 7 PM (11 AM PT) half-hour Channel 4 News to a full hour on the day. It will not be covering the wedding live. Channel 4 will, however, attempt to upstage William and Kate with a one-off of its reality TV show, Big Fat Gypsy Weddings, which has been a cult hit here. The channel will also be airing one-off docs about Kate Middleton’s family with TV historian David Starkey arguing that, in not marrying royal, William is in fact returning to tradition.

Five: Matt Barbet and Emma Crosby will be presenting news coverage.

Cinemas: Both Vue Cinemas and Cineworld, which between them have nearly 1,500 screens, have abandoned plans to show it. St James’ Palace, the official residence of Prince Charles, says the decision has nothing to do with it – pointing a finger at the BBC. The BBC in turn has suggested ITV and BSkyB have blocked cinema operators’ plans. Steve Wiener, CEO of Cineworld, tells me no reason has been given. Tim Richards, CEO of Vue, says it’s “a lost opportunity for the business and for the country”. Both Cineworld and Vue were hoping for a windfall, thinking people would want to watch the wedding with others as it unfolds in state-of-the-art sound and vision. The BBC tells me it scrapped its own plans to make the wedding available to cinemas outside the UK because it couldn’t get music rights cleared.