I don't understand why some people try to dream up a market while there actually is none. Why on "insert superhuman beeing of your choice here"s green earth would a lot of people replace their smartphones with a Pyra ?
It's not as pocketable as a phone, will be rather cumbersome to hold (even if natsus idea would be integrated), and even more cumbersome to use: you have to open the device if you want to see who is calling or if you want to dial a number, send a text message, browse your contact list, etc. And this probably won't even be "just" possible as someone would need to at least port the appropriate software to the Pyra. But even if someone steps up to do the job, why do you think it will give people a better experience in that particular field than a smartphone ?. And what about someone calling ? You would need a dedicated button for answering the phone - I know there are shoulder buttons on the outside, but you then need to implement a locking mechanism, so they don't accidentially get triggered, which in turns needs adjustments in the OS as this surely conflicts with the original intention of the Pyra: beeing an UMPC.
What about the price tag ? Why should "a lot" of people pay 500+ Euros for something that has already outdated hardware by the time it gets to the market, and its phone functionality is only a byproduct ? While they can have a phone that does the job better, has better hardware, and buying it probably won't "hurt" as much as they probably pay it through their contract.
The only reason I could think of is that they want to support the idea, and/or are interested in the community aspect. But how many of those are really there ? There is only a handful (5 or 6 ?)of people in that forum that stated they have interest in such a functionality, and I can think of only two that are actually trying to keep the topic alive. Should the Pyra team really go through all the costs (money, time, resources) just to please a super minorty in a niche?