Every AIR app I've run across (Flash or HTML based) has always ended up in the trash can. Either it's too slow, too obtuse, inconsistent user experience from the rest of my OS, etc. I find even the much flaunted Balsamiq to be inexcusably slow, so slow in fact I still prefer booting up XP in a VM and using Axure (which is better software anyways, but that's another topic for another day).
And I really wonder if these guys think they can do what Sun, Microsoft and - to a lesser extent - Adobe, have failed to do: build a cross platform UI toolkit without the aforementioned deficits. And then the filesystem abstractions and socket abstractions and the list goes on and on.
And, really, coding native isn't that hard on either platforms (I don't know much about Linux desktop dev, but I know plenty about Windows and just enough to shoot my mouth off with OSX). And it's not likely you're building anything of any serious complexity with AIR, Titanium, etc. anyways. I can almost guarantee you that I could build their example twitter client in Cocoa in roughly the same time and with roughly the same LoC metrics. I'm not saying that because I have a big penis, I'm just wondering what the true value of these cross platform tools are when they only deliver on a small percentage of what my particular OS has to offer.
It almost feels like you are sacrificing usability for a developer's laziness. For example, I built this in ~10 hours: http://videos.massify.com/prototype/shave.demo.mov - including the custom UI widget to visually create a video clip.
Anyways, cool work, nice demo, good luck!