i'd like to know this too. now that i have a phone that wasnt built inside of covered wagons heading to oregon i'm questioning all the online stuff.
box, google drive, picasa, etc..is there a best solutoin here? they all have pros and cons. i'm not real keen on cloud storage anyway.
regarding shutterfly, they recently changed some stuff and deleted some old photobooks i created which they said at one time they'd never do.
goes to show you stuff you are promised wont change..chnges.
also, the last time i was on shutterfly, 'guests' or people i gave access to only could get to shitty low-res versions of my photos so i'm not sure if that's a good solution either.
i would say picasa/google just given their popularity and deep pockets and philosophy.