Yahoo's (YHOO) new CEO, Scott Thompson, announced Tuesday that the Internet media company posted its first quarterly sales increase in three years.

But as Reuters noted, investors should hold their applause, because when it comes to profit, much of the company's increase came from earnings in equity interests, such as its investments in Alibaba and Yahoo Japan.

What's sad, BGC Partners analyst Colin Gillis told the news service, is that Yahoo's investments are generating more profit than its core business. "Their income from operations was about $169 million, and their earning and equity interest was about $172 million," Gillis said.

That's not sad; it's downright depressing. That means that Yahoo got extremely lucky and that its core business remains weak. It is much, much too early to speak of the Thompson turnaround.

While disposing of these investments will give Yahoo a much-needed cash injection, the company's problems go beyond just money. Yahoo is an unwieldy Frankenstein of a company that is trying and failing to be all things to all people. The latest quarterly results beat Wall Street's low expectations but were nothing to write home about.

Though Yahoo's net income rose 28% to $286.3 million, or 23 cents a share, from $223 million, or 17 cents, a year earlier, its revenue excluding traffic acquisition costs (TAC) rose 1% to $1.077 billion. Display revenue was $454 million, down 4% when TAC is excluded, which is not a good sign for Yahoo.

In the earnings conference call, Thompson spoke about his plans to transition or shut down about 50 properties. He didn't offer any specifics, but Venture Beat has offered some suggestions about what Yahoo should cut.

Earlier this month, Yahoo announced plans lay off about 2,000 workers in a cost-cutting move and has reorganized the company into three business units: consumer, regions and technology.

If Thompson can bring Yahoo back from the dead, he will have accomplished the greatest corporate turnaround since Lou Gerstner saved IBM (IBM) from bankruptcy in the 1990s. But he is a long way from that lofty accomplishment.

It's been said before, but I will say it again: One quarter does not make a trend.

Jonathan Berr does not own shares of the listed companies.