UPDATE: The question about whether Apple devices can show UltraViolet films is complicated, it seems. The folks at Warner Bros say that iPhones and iPads can handle them — but not through the traditional channel, the iTunes Store. Users must  download an app to also register with Flixster, a site that Time Warner owns. Movies can be streamed, but not downloaded yet. Sony’s likely to have a similar work-around for its Dec. 2 release of UltraViolet-enabled Blu-ray discs for Friends With Benefits and The Smurfs.

PREVIOUS, 10:50 AM: There’s still a fair amount of skepticism about the entertainment industry’s long-awaited UltraViolet program today as it kicks off with Warner Bros’ home video release of Horrible Bossesto be followed on Friday by The Green Lantern. The DVD and Blu-ray versions of Bosses will be first that make it possible for buyers to watch it on mobile devices from UltraViolet’s Internet cloud. Studios and consumer electronics companies have a lot at stake in promoting the “buy once, play anywhere” concept. It’s part of a process to slow the stomach-churning decline in home video sales. Consumers will spend about $16.9B on home video this year, down from $24.4B in 2004, SNL Kagan says. If UltraViolet catches on, then it also could give studios a lot of flexibility to control the way their films are presented and handled as consumers begin to abandon discs and just rely on digital streams and downloads.

The problem? UltraViolet movies won’t play on Apple gadgets such as the iPhone and iPad. The initiative also won’t include movies from Disney, which is preparing its own cloud-based system called Disney Studio All Access. “Not only is the ecosystem not fully launched, with a common downloadable file  format a ways off, but there has been no consumer education on the technological transition from a pre-UV world to the new UV ecosystem,” BTIG analyst Rich Greenfield says.The fine-print may overwhelm non-technophiles: UltraViolet enables up to six people in a household to link a movie to up to 12 devices, and it can only be watched by three of them simultaneously. So you can’t lend an UltraViolet digital file to a friend as easily as you can with a disc. Last month, Time Warner Cable CEO Glenn Britt told an investor conference that he doubts many people will warm to UltraViolet as it becomes easier and cheaper to rent films via VOD. “We know that young children like to watch the same movie until the DVD wears out, but most adults don’t watch the same movie that many times,” he said. Still, Morgan Stanley’s Benjamin Swinburne says in a report today that movie studios have a lot to gain, and little to lose, by trying to persuade consumers to buy instead of rent. “If UV can drive consumers to adopt a cloud-based film ownership model in any material way, stocks that have material studio assets would likely see higher earnings and multiple expansion,” he says.