Can somebody explain to me why there are so many mentions of "plugging into usb"?
From what I can see it's a PCI-E card, just like a GPU?
Also this would mean you could stick those into a normal motherboard, so why the need for a special fpga board?
From what I read a few pages back, it uses the PCI-E riser card to help with power (just like a regular GPU). The USB connections connect to USB ports though. Either on the PC/MB or on a USB riser card/hub.
Yes, you connect these FPGA cards to a 'normal motherboard'. The FPGA board replaces your GPU(s).