Online ad spending in the U.K. leapt 66 percent to £1.4 billion (about $2.4 billion) in 2005, according to new figures from the Interactive Advertising Bureau UK (IAB UK).

The numbers, based on a biannual survey of 78 companies performed in conjunction with PricewaterhouseCoopers (PwC) and the World Advertising Research Centre, show big growth in all areas of interactive advertising. Search led the pack with 79 percent growth to £768 million ($1.3 billion) during the year, display advertising grew 44 percent to £335 million ($584 million), and classifieds exhibited 62 percent growth to £262 million ($457 million).

The vertical array of spending hasnt changed a great deal. The recruiting and finance sectors were out in front for the second year running, with 22 and 17 percent of the market respectively during the second half of the year. Two big movers were the automotive and entertainment/media verticals, each of which grew its share of the total pie to about 10 percent.

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