GAURDiAN ST0RY...

The internet is set to overtake magazines to become the world's third largest advertising medium in 2010, according to a new report.

Media planning and buying agency ZenithOptimedia's global advertising report estimates that in 2010 the internet ad market will be worth almost $61bn (29.5bn), compared with the magazine market at around $60.5bn (29.3bn).

By 2010 the internet will account for 11.5% of global ad spend, trailing just TV, at a 37.5% share, and newspapers with 25.4% of an estimated $530bn (£257bn) total spend, according to Zenith.

Internet ad spend is currently ranked behind radio globally but will surpass the medium's share next year. In the more developed UK market digital ad spend passed radio last year.

The largest single internet ad market in money terms is the US, although the overall media spend share held by digital advertising in America is relatively low.

Digital ad spend growth will come from markets such as western Europe, says Jonathan Barnard, head of publications at ZenithOptimedia, a region which will go from £10bn this year to almost £20bn by 2010.

Other rapidly growing markets, while currently small, include China, which is predicted to grow from about £1.3bn now to £3.7bn in 2010.

In the more developed digital ad market in the UK, online already accounts for more than 15% of total advertising spend across all media.

However, ZenithOptimedia's report predicts that globally the medium will only break into a double-digit share of media spend - 10.4% - by the end of 2009.

Regions such as Latin America, for example, have been slow to shift spend online, accounting for around 2% of all media spend in the continent.

By 2010, however, internet ad spend as a share of all media will break the 15% mark in 10 regional markets around the world, according to ZenithOptimedia.

Currently just four markets have reached this milestone - Denmark, Norway, Sweden and the UK.

In these four markets the internet is predicted to top 20% of all media spend by 2010.