With each rise in Facebook's (META 2.53%) share price the past month, short interest in its stock has also increased. Nothing surprising there, of course; any significant improvement in an upstart growth stock's value is always subject to naysaying. But as I wrote in an article late last month, there are legitimate reasons behind Facebook's stock improvement.

And like last month's article, recent discussions between Facebook and Microsoft (MSFT 1.56%) regarding the software king's Atlas Solutions platform is confirmation Facebook has a plan to leverage its billion-plus users.

What's the deal?
First, a bit of recent history: Facebook already proved it's gotten serious about its advertising, with the announcement of its new sales tracking tool. The in-house Facebook ad measurement gizmo gives its customers a way to measure their return on investment, just like a real advertising company. The reason Facebook's homespun tracking tool is relevant is that it's confirmation of what Facebook is doing well: taking steps to become a leading online marketing alternative for business.

The Microsoft talks are Facebook's next step in its efforts to stand side by side with $225 billion online ad behemoth Google (GOOGL 1.55%), and its DoubleClick advertising service. In a nutshell, Atlas is a means of tracking, measuring, and utilizing digital advertising campaign data, across multiple platforms. Again, just like a real advertising company, Atlas would allow Facebook customers to track and analyze billions of impressions daily, then use all that big data to target future marketing efforts.

No word on what kind of dollar figures Facebook and Microsoft are bandying about, but from what those in the know are saying, the cost effectiveness of buying the solution vs. building it in-house has Facebook intrigued. What's intriguing for investors is that Facebook is discussing the purchase of Atlas at all -- in other words, once again taking initiative to play with the big boys.

Speaking of intriguing, the possibility of Facebook and Microsoft incorporating a shared advertising arrangement into the deal is being discussed. That'd be a pretty formidable partnership, and you know there's no love lost between the two and Google.

Insider sales? No problem
The release of 800 million shares Nov. 14 didn't cause a hiccup, other than Facebook's jump in share price, nor did the SEC announcement that relatively new board member and COO Sheryl Sandberg sold $26 million worth of Facebook shares recently.

The fiscal cliff may have led to Sandberg's sale. But even if it didn't, the upside for Facebook fans is neither Sandberg's trades, nor the stock lockup expiration, started a run on shares -- both bullish signs.

The challenges remain the same
The Google+ service, though still relatively new, has been growing at an alarming rate. As reported on Google's blog Dec. 6, more than 500 million users are on the service, and 235 million are "active." Outside of LinkedIn's (LNKD.DL) business networking efforts, no one comes close to Facebook's sheer user volume: Until now.

Along with LinkedIn and Google, online mainstays Yahoo! and AOL are both making significant strides in their (respective) efforts to become relevant online destination portals, and, by extension, even bigger online advertising competitors. How? Both Yahoo! and AOL are quickly turning into content kings, and ad revenues are growing as a result.

But Facebook is hardly done when it comes to maximizing its core asset: those billion users. The social jobs app announced on Nov. 14 is another step in the right direction. Though LinkedIn shareholders were not impressed, it offers real possibilities to further leverage Facebook's strengths. And the expansion of Facebook Gifts addresses Facebook's biggest concern of finding more and more ways to expand revenue streams.

The deal for Atlas, assuming the financials work, is a good use of what would be a small portion of Facebook's strong cash position of $10.5 billion. But even if the two industry stalwarts can't agree on the particulars, for Facebook investors it doesn't matter. Facebook's effort to expand its services says it all.