I haven't purchased the new Hornby bluetooth yet, but I do have a Blunami, and have a couple of thoughts on this.
The Blunami doesn't cost too much more than a Tsunami2, and for that price I can access all the settings using an interface that is much nicer than JMRI, and control 400 settings with well-organized sliders and auditionable sounds in realtime as I run my loco on the main. BlueRail has really put a lot of time into the settings interfaces. Also, JMRI is constantly giving me driver issues and won't work on most of my PCs (because I don't have the right version of Java or something). I don't think of this as obsolescence at all. Its just a really nice bonus to have access to these screens. I'm learning about features on my decoder I had no idea existed.
When I control the board via bluetooth, I can run the train from 50 meters. I use battery, and range is not a problem. If it does go out of range, it automatically reconnects the moment it comes back in range.
Because the Blunamis are bluetooth and DCC, the potential exists for a plastic throttle to connect directly to the boards and run them without a phone. The boards are becoming very popular quickly, so its only a matter of time before one of the popular throttle makers decides there are enough users out there to warrant adding a $10 bluetooth chip to a version of their plastic throttles and making a physical throttle. So you can use the throttle to run your train, or use the smart device to adjust settings (or do something a throttle isn't great at - like consisting).
Actually, my only wish was that Hornby and SoundTraxx coordinated their DCC bluetooth characteristic protocol so they aligned (so a throttle made for one could work on the other). They are just DCC packet bytes (but there are probably a few other extra little elements in each company's protocol that are different). Fortunately, the bluetooth boards support a wireless firmware update, so the potential exists to update the protocol at a later date.
I think arguing about obsolescence gets away from the fact that these boards offer nice added functionality while still being compatible. Just because they came out with automobiles with built-in radios didn't make the old cars obsolete. It was just a nice feature. They all still ran on the same road and could be controlled in the same way.
I understand the Blunami Android is supposed to release in a couple of weeks.