According to the biannual online ad spend study from the IAB, which is based on PricewaterhouseCoopers and World Advertising Research Centre data, online ad spend totalled £3.3bn in 2008 to command a market share of 19.2%.
In the first half of 2009, online ad spend rose 4.6% to £1.76bn, despite total UK ad spend contracting 16.6% during the same period. According to the IAB, this means online commanded 23.5% of all ad spend in the UK in the first half of 2009 - ahead of TV's share of 21.9%.
The IAB report reveals that paid search spend accounted for well over half of all online ad expenditure - £1.05bn - in the first half of 2009. Classified search spend rose 10.6% year on year to £385m. Online display was the only online medium to fall, dropping 5.2% year on year to £316.5m, and commanding an 18.1% share of all online ad revenue.
However, Thinkbox argued that if the TV industry pooled together all the money from broadcast TV to include areas such as spot, sponsorship and interactive, then last year TV's total ad revenue would, according to Ofcom, have totalled around £3.7bn. It noted that, based on IAB data, total online ad spend was £3.35bn in 2008.
Thinkbox added that if press added its classified and display ad revenues together then that figure would be bigger than both TV and online.
Lindsey Clay, Thinkbox marketing director, argued that "it is interesting but meaningless to sweep all the money spent on every aspect of online marketing into one big figure and celebrate it".
She added: "Online marketing spend is made up of many things, including e-mail, classified ads, display ads (including online TV advertising), and, overwhelmingly, search marketing. They should be judged individually."