Based on its 3% drop in share price since announcing earnings on July 29, it appears investors were less than impressed with Facebook's (NASDAQ:FB) second-quarter results. Surpassing the $4 billion revenue benchmark for the first time ever, increasing both monthly average users to just shy of 1.5 billion, and improving user engagement as measured by the nearly 1 billion daily Facebook visitors apparently weren't enough.

Despite the tepid response to Facebook's second quarter, the growth drivers that helped push its stock price near the vaunted $100-a-share level remain. Before investors jump off the Facebook bandwagon, here are a few things Facebook management would like to share.

Mobile and video reign supreme
Facebook's MAU growth last quarter was impressive, but the success of its mobile usage really stands out. A whopping 1.31 billion of its MAUs access the site via a mobile device, a 23% improvement over 2014's Q2. Mobile and video were constant themes throughout Facebook management's conference call, and it's easy to see why.

According to CFO Dave Wehner, mobile ad rates jumped a remarkable 220% last quarter. As Facebook's primary digital advertising competitor Google learned last quarter, investors are demanding a successful mobile effort. Google has long suffered from its lower cost-per-click results thanks to its slow transition to mobile-friendly ad solutions. Last quarter's impressive results were due in large part to Google rounding the mobile corner. Based on Facebook's Q2, it's already impressive mobile usage and advertising efforts are getting even better.

The impact of video ads on the jump in mobile ad rates wasn't specifically addressed, but it likely played a critical role. And based on COO Sheryl Sandberg's revelation that there are 40% more video shares today than just six months ago, combined with Facebook's ongoing video monetization efforts, it's safe to say both mobile and video will continue to drive future growth.

SMBs still rule
The majority of Facebook's more than 2 million marketing partners are of the small to medium-sized business (SMB) ilk, and Sandberg made it clear that's just fine. Sure, Facebook wouldn't mind securing more big-name brands, but SMBs are where its bread is buttered. One reason Facebook continues to spend heavily on ad tools is to not only enhance measurement capabilities, but to continue making it as easy as possible for SMBs to get on board.

As of Q2, Facebook boasted over 40 million SMBs with "active pages." With a "mere" 2 million or so advertisers, those 40 million SMBs offer a world of opportunity, particularly thanks to video. Of those 40 million SMBs, over 1 million have posted a video to their page. Those non-advertising video postings aren't generating revenue for Facebook today, but as SMBs become more comfortable with the process -- and the value - of video, that's likely to change.

Patience is a virtue
Naturally, the monetization of Instagram in particular, and WhatsApp and Messenger in general, were hot topics of conversation during Facebook's Q2 conference call. While Instagram is in the process of being monetized, and Sandberg confirmed what many of us assumed -- video will play a key role -- investors shouldn't expect WhatsApp's 800 million MAUs or Messenger's more than 700 million users to generate revenues anytime soon.

CEO Mark Zuckerberg asked "for some patience" as it relates to WhatsApp and Messenger until users ramp up the number of "business" interactions. As for Instagram, investors shouldn't expect to see a sudden revenue pop. Instagram, according to Sandberg, will "take time to have a significant impact on growth."

A couple of other items
As investors were forewarned, expenses jumped a staggering 82% last quarter. According to Wehner, the balance of 2015 will continue to see higher overhead thanks to infrastructure costs, hiring, and the development of ad tools but not quite as high as forecast earlier. On a GAAP basis (including one-time items), expenses are expected to rise between 55% to 60% this year, down slightly from Wehner's estimates the end of Q1.

Though sales and revenue targets weren't disclosed, Zuckerberg acknowledged that its Oculus Rift virtual reality headset is on track for a Q1 2016 launch. VR may seem like an after-thought relative to Facebook's video ad efforts and the monetization of Instagram, but the market is expected to total about $3 billion in just a few years -- and that's just for the hardware. Like Instagram, Oculus won't have an immediate impact on Facebook revenues, but the future looks awfully promising.

Tim Brugger has no position in any stocks mentioned. The Motley Fool recommends and owns shares of Facebook, Google (A shares), and Google (C shares). Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.