Looks like a promising product.
A plugin for VC won't happen any time soon.
1 - they are only available in the U.S.
2 - There would need to be sufficient demand (enough VC users who wanted it)
3 - They have no SDK/API at all so at the moment it is actually impossible.
http://revolv.com/developer/Most likely when they do come out with some kind of API it will be HTTP/REST based and you will at least be able to trigger scenes and control devices using existing VC actions. For me to create e plugin requires an investment of both hardware (assuming it is even possible to buy it in Canada), and a very significant amount of my time.
