The timing of my Sept. 5 article on Facebook (Nasdaq: FB) was, admittedly, a bit fortuitous. At the time, Facebook hadn't necessarily addressed the many concerns that plague Zuckerberg's baby. The lack of diversity in revenue lines, flooding the market with the unlocking of insider stock (and more on the horizon), and negative sentiment held over from May's botched IPO, were a few of the concerns.

So what made Facebook attractive in the beginning of September? As so often happens when bears run rampant, the selling of Facebook took on a life of its own. Facebook shares closed at $17.73 a share on Sept. 4, following an article in The New York Times blaming everything but the plague on Facebook CFO Dave Ebersman. At less than half the May IPO starting price, the negativity was getting out of control. Hence, the article.

So, what's changed?
An addition to shareholders enjoying the recent jump in Facebook's share price, investors should feel relatively upbeat about a string of announcements because they provide a basis for the appreciation.

Facebook's lack of a mobile strategy has been a problem from Day 1. Not just an inability to generate meaningful advertising revenues, but the lack of features in the smartphones apps. The announcement of a new texting feature designed specifically for smartphones will help address Facebook's mobile computing shortfall.

The new feature allows users to send and receive texts, along with Facebook-generated messages, via users' email ID. The new functionality comes in addition to Facebook's previously announced alignment with Google's (Nasdaq: GOOG) Android OS. Smartphones running Android can sync photos, utilize messenger apps, and receive updates.

Not all smartphones will have access to the new features just yet (Samsung and HTC, for example). But it shouldn't be long before the enhanced smartphone functionality is rolled out to the masses. A Facebook messenger update for use on Apple's (Nasdaq: AAPL) smartphones is also available, and addresses at least part of users' need for ever-increasing speed when accessing Facebook features via iPhones.

Even as Facebook takes on its shortcomings in mobile computing, it hasn't forgotten what I've long believed is an underutilized revenue-enhancing opportunity -- businesses. Capitalizing on Facebook's nearly 1 billion members, many of whom work for or own businesses, has a world of opportunities. If Facebook got the itch, adding LinkedIn-like (Nasdaq: LNKD) services for its already huge existing commercial client base isn't a stretch.

Before heading into the LinkedIn minefield however, Facebook has other commercial revenue-enhancing plans. As announced Sept. 21, Facebook will charge companies that post products for sale. And in a nice, cross-branding move, Facebook will up the online deals competition with Groupon (Nasdaq: GRPN) by providing these same fee-paying companies its Facebook Offers service.

In addition to earlier signings of Apple execs to help with the mobile computing shortcomings, former Netflix VP of engineering John Ciancutti has been brought on to head up Facebook's relatively new emphasis on business customers. LinkedIn, here we come?

Either way, Facebook is getting serious about better using its most valuable asset -- the aforementioned multitude of users.

Are these the ultimate answers to Facebook's challenges? Of course not; it's a big mountain and Zuckerberg and team still have a real climb ahead. As much as anything -- and this is what Facebook shareholders and potential investors should be (cautiously) optimistic about -- the recent steps are indications of a management team bent on addressing its shortcomings. Wasn't long ago that not many folks would have given Facebook even that level of consideration.

Now, don't be alarmed when another round of insider stock is released for sale this fall (a couple of billion shares, as a matter of fact). Concerns about flooding the market when the lockup period expires were somewhat muted by Zuckerberg's announcement he won't sell his 444 million (plus another 60 million he has access to) until at least September 2013. But that's near-term thinking, anyway. Over the long run, Facebook's recent moves to expand revenue lines and services will justify the September run-up (and the appreciation to follow).

If you're considering taking the Facebook plunge, particularly at these levels, more information is always a good thing. Take a look at another analyst's perspective in our special premium report on all things Facebook. You can review the comprehensive report, both the risks and upside potential Facebook offers, by clicking here now.