Probably about 100 which is the amount I took on my last outing .... I download the RAW files to the computer then format the card back in the camera.
I then process the files I want to keep, put the Jpegs on Flickr and delete the lot off my computer. If Flickr went belly up I would have nothing at all.
You need a backup plan.
, you really, really do.About 279,000 apparently.....4.11TB worth :|

You need a backup plan.