I can play a music file in the background while I search the net for a lyric, and keep a notebook window open in the background to instantly access a chord chart if need be. The iPad multitasks extremely well, and it's no where near "locked in" to iTunes ... it just shares better because of it. The program I use to play files can display lyrics, search the iTunes playlist, change key and tempo - REMEMBER the changes per tune and it stops after each song ... if you choose that option.
Apple/Bose people know what I'm talkin' about.