I recently bought a Droid and want to upgrade the default SD card that came with the phone. I know very little of the world of SD cards and want to know if there are any specific numbers/brands that will not work in the phone: Does it matter if it is SD or SDHC? Does it matter what class it is? (what is this, BTW?) Does it matter what brand it is? I just want to make sure I don't buy a card that doesn't work in the droid. Don't want to buy through verizon because they charge 3x as much as anyone else.