my upgrade is in april or june and im 100% going to get an iphone. but my concern is that the 16 gigs isnt going to be big enough! true i only have rougly 1 gig of music on my itunes library, but i want to future proof it! and 16 gigs seems small! if im adding videos, pictures, apps, music, contacts, calenders...etc, how fast is ya'lls 16 gigs filling up?