Digital media specialist Rovi (Nasdaq: ROVI) reported fourth-quarter earnings and sales that came in pretty much as preannounced six weeks ago. Analysts weren't surprised by pro forma earnings of $0.54 per share on $140 million of sales. So why is the stock falling on an otherwise positive market day?

Well there's always the guidance bugbear. For 2011, management sees adjusted earnings of $2.20 to $2.50 per share on about $800 million in sales, including contributions from soon-to-be-acquired digital video wrangler Sonic Solutions (Nasdaq: SNIC).

Add up the separate analyst forecasts for Sonic and Rovi for that period, and you'd get something like $2.60 of earnings per current Rovi share on $868 million in combined sales. While some inefficiencies are always to be expected when integrating two companies, that forecast falls far short.

Management spent a lot of time in the earnings call talking about Sonic Solutions and its expected impact on Rovi's operations. Movie store portal deals with Dell (Nasdaq: DELL), Sears Holdings (Nasdaq: SHLD), and Vizio were held up as high-profile wins for Sonic, and the deals should roll in faster as the availability of TV sets and Blu-ray boxes with Roxio store support ramps up in the second half of the year.

I'm a skeptic of Sonic's (or Rovi's) chances when it comes to becoming a digital video store powerhouse with its cookie-cutter service model. Between Apple's (Nasdaq: AAPL) iTunes store and the heft of (Nasdaq: AMZN) on the pay-per-rental side and Netflix (Nasdaq: NFLX) capturing the subscription audience, there's not much value in the Sonic store model. Big names might be signing up now, but I wouldn't be surprised to see cancellations rolling in as clients arrive at the same conclusion.

If there's any value in the Sonic deal, it would be found in the company's consumer-friendly media management software, which is a credible competitor to offerings from Apple and others. Let's see how long it'll take for Rovi to figure it out. Maybe Mr. Market is dumping Rovi's stock today because management doesn't seem to understand what it's really buying.

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