Originally posted by jatrax 8gb cards unless you do video. Less to lose if a card fails, or you drop it off a bridge. Also, usually (but not always) 2 x 8gb is less money than 1 x 16gb.
Many say that but i hold a different philosophy though.
I get a card that get me through certainly one day of shooting so that i don't have to switch card during the shoot/day.
You have less change you lose a card that way because you're too hasty or miss a shot because the card is full and you're switching it.
Another reason is that switching card will wear the SD holder in the camera out.
Also if you've more cards the changes of losing one will increase and the change that one gets damage.