Simplify the following text for a Grade 7 native English-speaking person.
Original: In October 2010 , Dave Grohl , former Nirvana band mate of Novoselic , announced live on BBC radio that Novoselic will be joining the Foo Fighters on their next album as a bassist and accordionist and it will be released sometime in 2011 .
Simplified: Grohl moved on to form the band Foo Fighters , and Novoselic has been mostly involved in politics .