Will updating itunes delete my music

With this being the case some of my music has been upgraded.Some of my music can't be upgraded and some of my purhased music is no longer even on the i Tunes Store because the label/artist never agreed to the i Tunes Plus format to begin with.

For me it's not that crazy at all and it's not the first time it has happened.

Legally you're still obligated not to distribute this music to all your friends, but music in this format is not physically restricted to only play on your authorized computers or only on Apple devices.