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The words "mobile" and "Facebook (Nasdaq: FB)" have historically not gone well together in the same sentence. Unless, of course, that sentence was: "Mobile is a huge weakness for Facebook." Here, let's try another sentence based on a recent report from The Wall Street Journal: "Facebook is expected to see mobile ad sales to soar by fivefold next year."

According to researcher eMarketer, Facebook's mobile-ad sales in 2012 will end up around $72.7 million, less than a 3% market share for domestic mobile ads and so far back that it can't even catch a glimpse of Google (Nasdaq: GOOG), whose Android platform has helped it dominate the mobile ad space with an estimated 55% slice.

I think Facebook could even bring in more mobile-ad sales than that, though, considering Mark Zuckerberg's comments on the last conference call that Sponsored Stories in News Feeds were already generating roughly $1 million per day in revenue, with half of that amount coming from mobile. That was as of the end of June, so mobile revenue of $500,000 per day for half the year comes out to roughly $90 million.

That's a rough calculation, but it shows that topping eMarketer's estimates would be possible. The researcher predicts that Facebook's mobile-ad sales will skyrocket to $387 million next year, more than five times its 2012 estimate, and enough to claim an estimated market share of nearly 9%. eMarketer analyst Debra Aho Williamson told the WSJ that after this year, "the experimentation phase will come to an end, and Facebook will figure out what works in mobile, both for the advertiser and the user."

Regardless of the specific estimates, the most important thing here is that Facebook is making progress on the mobile monetization front. That's long been derided as the social network's Achilles' heel and something of a dilemma as it focuses heavily on mobile development.

It also happens to play nicely with my wait-and-see thesis for Facebook shares, since I recognize the unparalleled potential the company has with its monstrous user base and accompanying data. You can read my full write-up in this premium report. Sign up today and you'll get regular updates at no additional cost, including if I think the time is right to buy Facebook shares for yourself.