I'd rather have it in tablet format with more screen instead of the blackberry keyboard, now that there are very light cheap bluetooth keyboards that are comfortable to type on. I'm using one right now with my phone, and it weighs about the same as the phone. There are smaller and lighter ones around too.
It's much better for extended typing than a screen keyboard or blackberry keyboard. For non-extended typing, the blackberry keyboard is a small enough improvement on the screen keyboard to not be worth permanently dedicating space to it.
Just make the tablet battery swappable and sign me up :).
I quite like the idea of a physical keyboard on the device but I agree it's not really the best for extended typing.
It does cover the use cases I wan't from a linux hand held up to a point. If I could dock it to have a real monitor when I'm not on the go it would be perfect. Maybe through a usb-c output ? Just so I don't have to fiddle with multiple usb/hdmi cables when I want to set up