Investors turned a cold shoulder to online video ad company Tremor Video in its first day in the market. Shares closed today at $8.50, down from the IPO price of $10. That was already less than it originally hoped to raise from the sale of 7.5M shares, with proceeds to help run the company. Many tech sector investors had their eye on Tremor, which accounted for about 4% of the $2.2B spent last year in the U.S. for in-stream, pre-roll online video ads. Although it’s in a hot business, Tremor is puny compared to YouTube, which has as much as a third of the market according to Pivotal Research Group’s Brian Wieser. “We think there will be some value in being a number two or number three player in the sector, as foil to Google or as acquisition bait from other web publishers,” he says. Tremor lost $16.6M last year on revenues of $105.2M.