Hi Jean,
The Z-Wave PC SDK is .NET-based, as is Mono--so the SDK will be designed for Mono on Linux and Mac OS X.
As far as the USB sticks go, different software companies support different USB sticks. We try to support as many of them as possible, so that you can create great solutions using the SDK and the USB sticks...
If there's enough interest, we could definitely make a Python bridge.
Chris