Facebook earnings: Here's what to watch

Facebook earnings in focus

Investors and analysts will find out how Facebook has fared over the past three months when the company releases earnings after the bell Wednesday.

Ad revenue and mobile are in the spotlight. S&P Capital IQ's Scott Kessler told CNBC's "Tech Bet" on Wednesday that mobile advertising is the single most important component to the overall mix of Facebook's revenues and earnings.

Kessler said mobile has become vastly more important than desktop.

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"This is a very, very significant opportunity for the company," Kessler said. "Not only is the growth there but increasingly the pricing has become more favorable. That really has been a very constructive recipe for Facebook in terms of revenue, growth as well as margins."

Nothing great comes without risks though, specifically WhatsApp and Oculus. Kessler isn't saying the deals won't work, but he said those deals are still "prerevenue" and "preproduct."

Kessler also told CNBC that Facebook is still very relevant even if data suggest the social network is losing its cool factor among teens. Kessler said teens consider it more of a necessary utility.

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