“What kind of memory card does the PS Vita use?”
Sony has a long history of shoveling their own proprietary media (betamax, minidisc, UMD) down our throats and the PS Vita is no exception. The PS Vita uses the “PlayStation®Vita card” to store all your saved game data, add-on data for games, downloaded games, music, photo and videos.
There is no internal memory in the PS Vita so you will need a PS Vita Card to do anything. The Playstation Vita First Edition Bundle does come with the PS Vita Memory Card but the non-bundle version does not.
Currently you can purchase 4GB, 8GB, 16GB and 32GB PS Vita Memory cards.