The good news is that $5.8 billion was spent in online advertising in the United States this past quarter, according to market watcher Interactive Advertising Bureau. That is the second-highest quarterly tally of all time.

The bad news? The best quarter ever happened three months earlier, when the industry rang up $5.9 billion in Internet sponsored revenue. It is the first sequential dip in three years for an industry that was supposed to be immune from the marketing malaise being felt in more old-school mediums.

Don't panic.

Some will argue that it is not fair to pit the typically sleepy first quarter against the seasonally charged fourth quarter, when retailers are bending over backwards to reach holiday shoppers. This past quarter's $5.8 billion take is a respectable 18.2% improvement over last year's first quarter.

However, the fact that the industry can no longer overcome seasonality to score sequential gains is a fair indicator that either the niche is maturing or that it is not so adept at shaking economic hiccups.

Thankfully for investors, you don't have to buy into entire sectors. For every Yahoo! (NASDAQ:YHOO) or CNET Networks (NASDAQ:CNET) or Marchex (NASDAQ:MCHX) that isn't growing as quickly as the market, you have a Google (NASDAQ:GOOG) or IAC's (NASDAQ:IACI) that is.

Google posted a year-over-year revenue gain of 42% during the quarter, and a reasonable 7% sequential advance. The results may have been peppered with headier growth overseas, but Big G continues to be a stateside force by nibbling away at overall market share.

In short, don't freak out over the sequential dip. Latch on to the growers. The valuations are still attractive.

Now, if you see IAB report that fourth quarter ad revenue took a sequential dip early next year, that is when you run for the hills.