Google is testing new ways of putting advertising on its websites but insisted this will not detract from users' experience of its services.

Joanna Shields, the Google European director of syndication and partnerships, said the media giant is trying to find different ways of inserting brands into its content.

"We're testing new ways - what's the right kind of advertising and what works and what doesn't. We're also working with MTV, streaming their content," she added.

Both Ms Shield and Jamie Kantrowitz, the content and marketing senior vice-president for MySpace, denied that they were debasing the value of their products by putting on more advertising.

Instead they said the issue was about ensuring advertising is targeted properly.

Ms Kantrowitz said: "The truth, especially for a young person growing up, is they define themselves by brands. They identify with them and say 'I love Lost' or 'I love Nike'.

"I think it is OK if you insert a brand into a piece of content. If they can't find it, they will create it."

Celia Taylor, the controller of Trouble and Challenge, said that while she would not try to sell her viewers and users life insurance, "our audiences don't mind being targeted by Nike".

All three RTS London conference panellists said traditional media, such as TV and film, need not fear too much as people who make user-generated content or chat on social networking websites are often doing so around or making reference to this more traditional content.

Ms Kantrowitz said: "People still mostly watch DVDs and films. They have a bunch of brand champions dialoguing about what you've made."

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