Sony has once again opted for expensive proprietary memory with these new Vita flash memory cards. These cards will
be neccessary for storing the games themselves if you decide to go down the digital route and purchase games directly
from the PSN Store, as well as the game's save files, and future updates or patches. They'll also be used for any photos,
music or video you want on your Vita because the device itself has no built in memory.
Considering the maximum memory card available right now is just 16GB, it's likely you'll need to purchase multiple cards
if you want games from the PSN Store, and also want your media on the Vita (current games range from 200mb to 3GB in size).
The main issue is that the cards are overpriced, i'm fairly confident that cheaper brands will appear, but Sony should
know better. Another problem is that the cards are tiny and easy to lose, and switching between cards is very fiddly
(you'll probably need to switch between cards if you need more space or if a save file is on a different card, but also
switching cards allows you to use different PSN ID's - it's currently the only way of using more than one PSN ID).
But if your not going to have any media on your Vita and will be purchasing all your games via retail in boxed copies,
you can pretty much sidestep these overpriced cards. Each Vita game will come on its own memory card with enough space
to store your save data. This won't work for games which explicitly require a memory card like Uncharted Golden Abyss.
So although buying at least one Vita memory card is necessary, depending on how you will buy your games, how much media
you want on your Vita, and whether or not you want to manage multiple PSN IDs will influence what size card you need.