It's backwards compatible with PCMCIA (well, the slots are anyway) but Cardbus cards are 32 bit cards, similar to PCI. If your notebook supports it, Cardbus is almost always the better choice.
Aye. Physically the slots are identical. Cardbus slots can run either 16 or 32 bit cards, cardbus cards can't always run in a non-cardbus slot (some dual-mode cards exist).
