These are suddenly anxious times for the media economy, with just-released figures for the first quarter showing that ad spending actually dipped, falling by 0.3 percent.

But you would not know that from looking at the latest numbers for online ad spending for that same three-month period. Spending rose by 26 percent from January through March, to $4.9 billion, compared with the year-earlier period, setting yet another record.

That's according to the Interactive Advertising Bureau and PricewaterhouseCoopers. That's a 2 percent increase over the last quarter in 2006.

That pace is somewhat slower than in past quarters but still very robust and in line with forecasts. Full-year 2006 online ad spending rose 35 percent, to $16.9 billion, double what was spent in 2003. First-quarter 2006 grew at a pace of 38 percent

By contrast, traditional media has been bumping along. The latest figures from TNS Media Intelligence show that in the first three months of 2007 three major categories suffered declines in ad spending, with TV down 2.7 percent, newspapers down 4.7 percent and radio down 2.1 percent. Magazine ad spending was up 4.4 percent and outdoor up 2.4 percent.

Continued internet ad growth reflects the ongoing shift of ad dollars from traditional media, with mainstream advertisers drawn by the internet's accountability and cost efficiency.

There has been talk in recent years that the pace of internet ad growth must slow at some point, if only because it's growing from a larger base, but when the slowdown might come is as unclear as ever. Peter Petrusky, director of PricewaterhouseCoopers, believes brisk growth will continue for some time, as more users access the web via broadband.

Early this year, eMarketer put out a forecast predicting that internet ad spending would slow to 18.9 percent in 2007. The forecast called for internet ad spending growth to then rise to 22.1 percent in 2008 -- a year where political and Olympic advertising should be strong -- before dipping a bit for several years.

EMarketer gave two reasons for the slow in 2007, the first being the ever-widening base of spending, which makes huge percentage increases harder to sustain. But the other reason cited by eMarketer was its expectation that the U.S. economy would soften this year, which, indeed it would seem to have done.

This softening would filter through the media economy, eMarketer forecast, eventually hitting internet ad spending.