From the Poser 7 ReadMe...

Since Poser 6, one Poser Native Unit always is the equivalent of 8.6 feet or 262.128 centimeters.

Personally, I prefer metric units... I am used to them :-)
I can enter logical values when setting displace or bump values in the material room,
can work with numbers I know when setting camera parameters, etc.

 

Yesterday's the past, tomorrow's the future, but today is a gift. That's why it's called the present.