Yahoo! gave some cheer to fickle stock market investors after announcing better-than-expected third quarter figures last night.

The web company’s shares jumped 10% after it posted a 12% increase in revenues to $1.77bn and had some good news to report from both its search and display ad businesses.

It generated a 20% increase in the key metric of revenues per search, while its display ad offering – the subject of serious investment by the company this year – saw revenue growth jump to “nearly 20%” after five quarters of deceleration.

The company said the figures (pdf) showed that its restructuring, recent acquisitions and new search ad system, Panama, were starting to pay off.

But its net profit was down 5% to $151.3m and ad revenues from its third party publishing partners dropped 1%, despite efforts to increase the reach of its search and display ad networks.

American Technology Research analyst Rob Sanderson summed it nicely to AP:

“Things certainly seem to be moving in the right direction. Now the question is can they string a few quarters like this in a row?”