The commercial real estate market is starting to get woozy, but you wouldn't know it from a first glance at LoopNet's (Nasdaq: LOOP) latest financial results. Fourth-quarter revenue soared 41% to $19.6 million. Earnings clocked in at $0.14 a share, ahead of both the $0.13 a share LoopNet earned a year ago and the $0.12 a share the market expected.

Don't be small-f fooled by the meager bottom-line gain at the leading online marketplace for commercial real estate listings. The company is being taxed at a higher rate these days. Go back a few lines to pre-tax operating profits, and you'll find LoopNet growing by a respectable 31%.

That's impressive, because despite the favorable spurts, LoopNet is actually already starting to feel the credit crunch, which is slowing transactions in the sector. Sure, LoopNet has 2.6 million registered members -- up 45% over the past year -- but the number of premium subscribers actually dipped compared to last quarter's numbers.The company is also feeling the sting of higher cancellation rates and lower views per member.

Don't assume that LoopNet is toast. A tricky environment is actually forcing sellers to spend more on LoopNet memberships. There are now 560,000 total commercial listings on the site.

LoopNet has also now topped Wall Street's profit targets in each of its first seven quarters as a public company. The same can't be said for other online lead generators, like Bankrate (Nasdaq: RATE) in interest rate products or The Knot (Nasdaq: KNOT) in the wedding space.

There are difficult times on the residential side of real estate. Shares of Web-based players like HouseValues (Nasdaq: SOLD), ZipRealty (Nasdaq: ZIPR), and Realtor.com parent Move (Nasdaq: MOVE) are all trading in single digits.

The next few quarters will also be challenging. LoopNet expects earnings between $0.45 and $0.48 a share this year, slightly less than the $0.52-a-share profit it generated in 2007. Revenue growth will continue, but at a slower pace. LoopNet predicts $84 million to $86 million in revenue, resulting in top-line growth between 19% and 22%.

Shareholders may want to keep a close eye on the company's premium subscriber count. Continued deterioration there will force LoopNet to rely more on ad revenue, and possibly break from tradition long enough to cut rates. That may be what eBay (Nasdaq: EBAY) is doing this year, but a young speedster like LoopNet shouldn't want to follow suit.

To read David Gardner's original buy report for LoopNet in the Rule Breakers newsletter service, take advantage of a 30-day guest pass. Bankrate and The Knot are also Rule Breakers picks. LoopNet is also a three-time Hidden Gems recommendation. eBay is a Motley Fool Stock Advisor selection.

Longtime Fool contributor Rick Munarriz has never dabbled in commercial real estate outside of the Monopoly board, though he can hand you Boardwalk and Park Place at the beginning of the game and still beat you. He does not own shares in any of the companies in this story. He is also part of the Rule Breakers newsletter research team, seeking out tomorrow's ultimate growth stocks a day early. The Fool has a disclosure policy.