The consensus as of late seems to be that while ad sales have been down, they are stabilizing. Benchmark Capital analyst Clayton Moran says not so fast. In a report this morning on Google (NSDQ: GOOG), he says that his “channel checks” show that while there was indeed an upswing in sales activity in March through mid May, sales in the summer months will drop back again. “Street sentiment has turned positive as economic indicators and online ad trends stabilized in April, but more recent online activity indicates a further pull-back by large advertisers,”  he says.

Moran says that could be due to to “exaggerated seasonal softness.” With consumer demand expected to be particularly weak during the summer months, advertisers may be cutting further back on spending. Moran says he is not alone in his view, citing Yahoo (NSDQ: YHOO) CEO Carol Bartz who warned last week that it was too early to call a bottom yet.

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