You didn't mention micro-usb. I have within one meter of me, devices that require USB type A ("regular"), USB type B ("square"), mini USB, micro USB and an iPhone.
I've got various Card readers, HDDs, Hubs, etc. that take Mini-USB B, but I've never seen Mini-USB A or any of the micro ones in the wild. Apparently Micro USB will be used for charging mobile phones henceforth.
