I just bought a new 2GB SanDisk Extreme III CF card. When I formatted the card, it showed 258 remaining shots (Jpeg SHQ). My old Belkin UDMA 2GB card shows 256 shots after a format, while the 2GB Olympus Type-M XD card shows 264 shots.
While I recognize that the camera is showing an estimate of the available exposures remaining, Why are the 3 figures different?