Not in the manual, at least not that I can find. But then it seems like all electronic devices these days are viewed as an Adventure Game.
It seems to be there, "Find help" briefly mentions it (last paragraph of the first section "In-device help"), and "Shortcuts" starts with it.
(Of course I am cheating, I have searched for switch in the .pdf version, http://europe.nokia.com/support/prod...ssmusic/guides)
That says nothing about "Task Manager", or how to long-press the app icon to bring up the close option.