Shouldn't you pay some fee to use the 'X' with the 'Bee' in this post?
I note that the designers studiously avoid using the term!
Personally I never had enough spare cash to spend to try out the system, also I wasn't pleased about the refusal to make membership of the zigbee alliance compatible with the GPL. That pretty much killed my interest, and so now I am happy to see it slide slowly into obscurity.
But hey, if you've got a dev board or other project with one of those headers you want to use it for, I suppose it's good to have another module.