It is basically the same thing. The minus of the PCMCIA version is that it sticks out of the laptop and runs the risk of getting broken. MiFi is nice, except the total energy used is greater (two extra wifi radios to power) so if one is often in places with limited/no power outlets, that may be a problem. And the big minus of this thing, is unless you somehow attach it to the laptop, it's a bit of a kluge to move around / travel with.

So each has good and bad qualities, it's all about what makes more sense for your travels. In this particular case, I would imagine the hotel went with the USB version because USB ports are found on all modern laptops (while WiFi and PCMCIA are not).