ID property access from python for pose channels, bones and any ID objects.
The advantage with this is that global property definitions are not needed to add a property to an object.
to avoid confusion these are accessed like a dictionary (closely matching how the BGE accesses properties)
ob["mySetting"] = 1.0
bone["foo"] = {"one":1, "two":2.1, "three":"Three"}
if "foo" in bone: print("prop found...")
At the moment these can also be accessed as attributes, will be changed shortly. eg.
bone.foo == bone["foo"]