NEW YORK: US adspend in UGC (user-generated content) websites such as YouTube, MySpace and Facebook is set to reach $4.3 billion (€3.1bn; £2.1bn) by 2011, predicts online researcher eMarketer.

The figure is a 330% hike on the $1bn expected to be spent this year on sites whose popularity centers on UGC.

Hypes eMarketer's report: "The nearly tenfold increase in [UGC] advertising spending in the US reflects optimism in the ability of companies . . . to continue to build and retain vast audiences."

By 2011, the researcher estimates there will be 95 million web users creating content online, up from 64m last year.

EMarketer also believes that annual adspend on social networking sites (like Facebook and MySpace) will soar to $3.6bn in 2011, up from the $445m spent last year. By 2011, spending on these sites should account for nearly 7% of online advertising.

Data sourced from Adweek (USA); additional content by WARC staff