Should you rush out and buy the largest size possible? Consider these thoughts before you buy.
A 2Gb memory card will store approximately 256 images from an 8 Megapixel camera. 256 images is a lot of images, but think about it like this; what if you lost that card with over 250 photos on it?
Memory cards are small, they can easily be mislaid or dropped or they can slip through holes in pockets bags or cases.
Memory cards are susceptible to static and can have their contents corrupted due to damage, heat, water, magnetic fields, camera problems and more.
My suggestion: buy four 2Gb cards rather than one 8Gb card. One lost or damaged card means you can still keep taking photos as it is not your only card. One lost card also means the loss of only one quarter of your pictures. Losing any photographs is bad but if you're at the end of your holiday or your photo shoot, imagine losing everything. If your photos are on several cards, at least you still have some shots to remember your vacation or to show to your client.