ok.. i am 3G 8GB user..i still left 4.27GB in my iphone.. I am not heavy multimedia user.. The peak time i have was 3 movie in my iphone.. Still have 1 movie now in my iphone.. And i have 7 Song's album on it...
If u are heavy multimedia user, then go for 16GB.. this means that u can have 10 movie & maybe 20-30 albums i guess..