- OS integration (launch external applications, run as service);
- multi-threading;
- PDF support;
- access to USB / Bluetooth devices;
- support on mobile devices;
Another one project to extend AIR application is FluorineFX Aperture (for Win platform only). I didnt tried it yet, but list of features looks very impressive:
- Launch native applications and documents;
- Take screenshots of the whole screen;
- Access Outlook contacts from an Air application;
Regarding multi-threading issue I found question on Flex cookbook: Is multi-threading possible in Flash or ActionScript?
I think, the rest of issues are not a big deal for Adobe :)