Online real estate specialist Zillow (NASDAQ:ZG) just announced second-quarter results, and boy, were they impressive.

Credit: Zillow.

To be sure, Zillow's quarterly revenue jumped 68% year over year to $78.7 million, easily exceeding analysts' estimates for sales of $76.5 million. However, that translated to an adjusted loss of roughly $2.1 million, or $0.05 per share, which was slightly wider than the $0.04-per-share loss Wall Street had predicted.

So why the bottom-line shortfall? Zillow affectionately blamed its 56,818 Premier Agent advertisers -- of which 3,850 were added in Q2, by the way -- who each spent an average of $320 with the company during the quarter, up from $266 in the same period last year. As a result, Premier Agent revenue and bookings grew by a record 82% and 101%, respectively. Because of those record bookings, however, sales commissions were $0.9 million higher than Zillow had originally projected, which resulted in an increase to its second- quarter net loss by $0.02 per diluted share. That's fair enough, and investors shouldn't fret, as most of the revenue related to those bookings will be recognized in future periods.

But that's not all that drove Zillow's record results. In fact, Zillow saw record quarterly and all-time traffic in Q2, with 49% growth in average monthly users to 81.1 million. That performance was capped by a new monthly record in July of nearly 89 million unique users on mobile and Web combined.

Mobile, in particular, saw the most impressive growth, with visits to Zillow on the fast-growing medium nearly doubling over the same period last year. In July alone, over 568 million homes were viewed on Zillow using a mobile device, or around 212 homes per second.

Zillow is seeing impressive growth in traffic from mobile devices, Credit: Zillow.

Better yet going forward, Zillow increased its full-year outlook and now expects 2014 revenue of $321 million to $323 million -- or growth of 63% -- up from its previous guidance range of $304 million to $308 million. In addition, Zillow raised its outlook for adjusted EBITDA to a range of $52 million to $54 million, up from its previous range of $48 million to $50 million.

And for those of you who want to look even further down the road, let's not forget Zillow's pending $3.5 billion acquisition of its largest online competitor, Trulia (UNKNOWN:TRLA.DL), a deal that's expected to close in 2015. Trulia, for its part, similarly grew its monthly unique users by 48% to 51.6 million last quarter, which resulted in 116% growth in revenue to $64.1 million. Once again, however, that growth came at the expense of profits, as Trulia simultaneously turned in an adjusted net loss of $4.2 million.

Even so, and while both Zillow and Trulia's lack of profitability has elicited skepticism from bearish investors, I'm not particularly concerned, as the two companies can now join forces as they strive to grab additional share in the burgeoning real estate market by first growing their top lines. Sure, shares might look expensive, trading around 164 times next year's estimated earnings and 25 times trailing-12-month sales. But as Zillow pointed out in an SEC filing shortly after the acquisition was announced, "the two companies' combined revenue currently represents less than 4% of the estimated $12 billion real estate professionals spend on marketing their services to consumers each year."

Over the long term, if Zillow and Trulia can grab any meaningful chunk of that overall market as real estate buyers and sellers continue to flock to their respective websites, patient investors stand to be handsomely rewarded along the way.