While slightly more than half (51%) of 1,599 advertiser and agency executives surveyed by API plan to boost their online advertising budgets over the next six months, that figure is down from 68% two months ago, and 72% a year ago.

"They're still optimistic, but they're not as optimistic," said Ken Pearl, a partner and co-founder of API, which conducts semiannual media customer satisfaction studies among advertisers and agency executives. API traditionally measures advertiser optimism as part of those studies, but following the economic meltdown, opted to conduct bimonthly optimism surveys throughout 2009 to track the vitality of the advertising marketplace for the major media.

The most recent survey suggests that the degree of ad budget pessimism may have bottomed out, or at the very least, is leveling off. The average for all media shows that 29% or ad executives expect to increase and 29% expect to decrease their ad spending over the next six months. That's a marginal improvement from two months ago, when only 26% planned to boost their budgets, while 30% planned to cut them.

Effective with the most recent survey, API has also begun surveying ad executives on their ad spending plans for online display and online search advertising.

Interestingly, the ad industry appears to be marginally more optimistic on the online display marketplace. Fifty-three percent of the respondents said they plan to boost their online display ad budgets over the next six months, versus only 49% who said they plan to boost their online search advertising budgets.

The outlook for mobile media also looks bright. Fifty-three percent of ad executives said they plan to boost their mobile advertising budgets -- the same as a year earlier, and up slightly from two months ago, when only 51% planned to boost their mobile ad budgets.

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