NIGHTWISH frontwoman Anette Olzon makes a guest appearance on "October & April", the new single from Finland's THE RASMUS, which is scheduled for release on November 11. The song, which is available for streaming below, has been sent to radio stations in Europe and the video for the track will premiere on October 23.

In a September 2008 interview with Italy's Musica Metal, THE RASMUS singer Lauri Ylönen stated that the idea for the song came to him nine years ago when Tarja Turunen was still the lead singer of NIGHTWISH, but he only got around to recording the track during the sessions for last year's "Black Roses" CD. "I actually asked Tarja, but she said no!" Lauri revealed. "Then I called Anette, and she was like, 'Yeah, I would love to sing a song with you, I'm a big RASMUS fan, actually two years ago before I joined NIGHTWISH, I was singing THE RASMUS songs in karaoke bars!' so we went with her."

"October & April" was not included on "Black Roses" because the CD was a concept effort and the song didn't fit in with the overall idea for the album. Instead, the track will make its debut on THE RASMUS' "Best of 2001-2009", a compilation of all the hit songs from their four latest albums, including the million-selling "In The Shadows", most of the singles and a few rarities.

Due on November 25, "Best of 2001-2009" features the following track listing:

01. In The Shadows
02. No Fear
03. Guilty (U.S. mix)
04. October & April (featuring Anette Olzon)
05. First Day Of My Life
06. Livin' In A World Without You
07. F-F-F-Falling
08. Chill
09. Immortal
10. Justify
11. Shot
12. Funeral Song
13. Ghost of Love
14. Open My Eyes (acoustic version)
15. In My Life
16. Ten Black Roses
17. Sail Away

Commented Lauri: "We felt it was time to sum up these past ten years. Eero said, let's call the album, 'This is how I spent my twenties.' No matter how stupid it sounded, that is pretty much the truth. We went on this crazy rollercoaster ride; it has been an amazing time. We have travelled to more than 60 countries, from India to Siberia, met thousands of fans all over the world and enthusiastic people working with our records. And when I look back on these last four records, I feel very proud of them. We decided to include most of the singles to the album with a couple of our favorite album tracks, and the new song 'October & April'."