A vibrant housing market continues to benefit Zillow (NASDAQ:ZG), which on Friday released its Q4 and full-year 2014 results. The young but very ambitious company posted encouraging growth in several line items and gave a crucial update regarding its acquisition of Trulia (NYSE: TRLA). Here are the key developments and numbers from the firm.

A stronger foundation
Zillow posted very encouraging gains in several important line items. Its total revenue of just over $92 million for Q4 notched a new quarterly record for the company, and was up a chunky 58% on a year-over-year basis.

Much of this was due to advances the company made in its core businesses. More people visited Zillow.com; it recorded a 41% increase in average monthly unique visitors, to 77 million. The important mobile segment grew by an impressive 57%, to the point where almost two-thirds of visits to the site came from such devices.

Regarding the bottom line, the company lost nearly $11 million ($0.27 per diluted share) during the quarter, in contrast to the $2.7 million ($0.06) profit of Q4 2013. On an adjusted basis, however, it netted a profit of $10.4 million ($0.24) against the year-ago period's $8.1 million ($0.19).

For the quarter, revenue beat analyst expectations while adjusted per-share profit fell a bit short. These were projected to be $90 million and $0.28, respectively.

As for the full year, revenue came in at just under $326 million, or 65% higher than the 2013 tally. But net loss was also much steeper -- nearly $44 million versus the previous year's $12.5 million. Similar to Q4, on an adjusted basis bottom line was in the black at $15.2 million ($0.35), up from 2013's $7.2 million ($0.18).

Out of escrow
But for many investors, the more important development was an update on Zillow's purchase of fellow real estate portal Trulia.

First announced last August, the buyout (to be paid for with roughly $3.5 billion worth of stock) has been making its way through the system slowly, with the Federal Trade Commission taking several months to investigate the particulars of the deal.

Apparently, the wait is over. Zillow said in its release that it received notification from the FTC that the regulator had closed its investigation. As a result, the company said it could close the transaction early.

Although few expected that the FTC would have serious issues with the tie-up -- the online real estate space is still packed with plenty of competition, even given the size and scope of a Zillow-Trulia deal -- news of the approval is a relief for each company's shareholders. Now the work can begin to fuse the two companies, although both maintain that Trulia will operate as a separate brand within Zillow.

Movin' on up
Following the announcement, which was released after market close on Friday, Zillow's stock price rose by nearly 6% in after-hours trading. That was almost certainly due more to the Trulia news than to fundamentals, which weren't too far off the market's expectations.

Going forward, investors should keep an eye not only on how the Trulia integration proceeds, but whether Zillow will be able to keep its key numbers rising. It's going to have plenty of work to do with its new asset; hopefully that won't affect those improving fundamentals.