It’s been reported on Rock in Rio website that McFly has been confirmed to perform on 2010 Rock in Rio, both in Lisboa (May 29th) and Madrid (June 6th).
Check out Rock In Rio website for more info.

Click on more to see the articles (automatically translated – sorry for any grammar, translation, or spelling error):

Rock in Rio-Madrid

On 6 June, Family Day, where all the music program is designed for the enjoyment of the young, British act McFly. That same day Miley Cyrus act in the same World Stage.

The confirmation of McFly at Rock In Rio will surely make the thousands of fans, that the British quartet already has in our country, go crazy. In England, the band has taken from the Beatles’ own historical record as the youngest group to debut at No.1 in the country. The Beatles hold this record for almost 20 years. McFly. The revolution grows mainly on the internet where 100 million people have already visited their official website with 11 million views of their songs on MySpace. Such a furor generated by this band between the younger, who planned the 2010 Fox film starring the band!
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Note: The Fox film has been rumored for some times now. As far as we know, it has not been confirmed by McFly.

Rock In Rio-Lisboa

McFly and D’ZRT will be present in the largest music event in the world. The British pop boy band and Portuguese working in the World Stage on May 29, the day dedicated to young people of the Rock in Rio-Lisbon 2010.
McFly started his musical career for six years and has managed to put seven singles and two albums in the first place the TOP English. The British have on your resume four albums of originals: the success of “Room On The 3rd Floor”, their debut album, made not appear in the Guinness book for being the youngest band ever to come with a photo directly of a first place for the TOP. And in the history of music, the Beatles had only managed to achieve such a feat.
In subsequent years, the edited McFly “Wonderland” (2005), “Motion in the Ocean” (2006) and “Radio: Active”, all big blockbusters. In total, the band has earned 3 platinum albums and 1 gold in the UK and won the Brit Award for “Best Performance Pop”.
McFly are presented for the first time in Portugal live at Rock in Rio-Lisbon 2010 and promise to make a big concert for all fans who long for his debut lands.
McFly and D’ZRT thus confirm their presence on the World Stage, the day dedicated to family, to present their fans with the subjects they know well.
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Thanks Mission McFly Germany, McFly Spain, and mission:McFly