hmm.. okays. sorry for my bad. i used to thought it was license thing about iphone...
as we all know apple very take serious with license thing... even bluetooth also cant transfer song....

then when i saw this software license agreement, it freak me out as i thought it is like software license thingy...
and also maybe i got wrong info from somewhere, either i heard it from somewhere or i read it on somewhere that when you sync your iphone into 1 pc... then u cant sync to other pc already... so this is where it lead me to think that my iphone once sync with itune in my pc it wont able to sync with any other pc due to the license thingy. so we wont able to here copy there copy and sync our iphone to all pc here and there....
so.. okays since i already know after sync my iphone with my comp pc there is no such thing as license thingy and i can format anytime...

well.. just to double confirm, so does it means i can just sync my iphone to multiple pc??? pc at my home, pc at my office and my laptop. i can just sync all of them with no worries???
thanks for all those helpful replies above... after so long now only i can get my iphone to hav some songs. >.<

hmm... wat u mean by same file as the pc im using???
i thought once i copy a song/movie file into my iphone, then the song/movie files is there ady???

will it dissappear if lets say i change name/location of the song/movie file in my pc???
or even if i delete the song/movie on my pc?? will the song/movie file still inside my iphone??