The main knock against Facebook in financial circles has been its inability to prove that it can be a solid buy for investors, especially in the way of mobile monetization. However, stock analysis firm Trefis thinks that Facebook has done enough in this field, and should be able to share a positive outlook in its fourth-quarter earnings call Wednesday.

Facebook will share its findings and give statements about the future of the company in a webcast Wednesday at 2 p.m. PT.

In a guest post on Forbes, Trefis wrote about how Facebook has made enough strides as a mobile advertising vessel to become worthy of investors’ confidence again. Trefis also likes Facebook’s potential in the future, as Instagram becomes more and more integrated into the social network.

The firm noted that Facebook will likely use Instagram to boost its own photo offerings and tap the photo service’s user base to drive engagement on mobile applications. Trefis wrote that the impact of Facebook’s acquisition of Instagram should really start to show with the fourth-quarter report.

After Facebook went public last year with an initial public offering price of $38, the stock value tanked, but it has rebounded and has settled at around $30.

Trefis wrote that it has been impressed with Facebook’s progress on mobile, which was a sticking point for many agencies that were hesitant at first to give the social network positive ratings:

We expect the company to make significant progress in ramping up mobile ad business in the fourth quarter. The number of ads within Facebook’s mobile feeds has increased significantly, and their effectiveness is also driving ad pricing up. The company launched a huge mobile advertising campaign for Walmart during the holiday season. About 50 million ads focusing on deals and discounts were rolled out to millions of Facebook users. Although the results were mixed, this marks an important step toward strengthening the monetization of Facebook’s mobile platform. While there was a high level of user engagement, the users also complained about unwanted ads.

Readers: Do you think Facebook has done enough to be worthy of a buy rating?

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