If you have not tried their sdk, I highly recommend it. It is open source(not free though). You can play around with it for free but if you want to use it commercially you need to pay.
How does it compare to other architectures? What sort of problems does it excel on? Where are it's weaknesses? What is the training like compared to other methods?
I wouldn't really take them seriously until a paper is linked to from their front page explaining the above. At the moment it just looks like hype.
http://numenta.com/for-developers/education/htm-related-pape...
Unfortunately the three (why aren't there more?) independent papers didn't use HTM, and certainly don't answer all my questions.