One thing my new MacBook won’t have is a PCMCIA (PC Card) slot. I’ve been rather fond of this on my old Powerbook – a CF card adaptor lives there permanently, and it means that I can always get photos off my camera without the need for cables.
The new machines have an ExpressCard slot. This is the replacement for the old PC Card standard; it has been around for a while and has lots of advantages, but I haven’t seen any cards for it yet, and the slot is too small for a Compact Flash adaptor, so it’ll be back to cables, I guess, for transferring my photos.