So before I even go into this blog entry - how many people think we are going to have a ton of "air" puns now that Apollo has been renamed???
So that aside, the very cool (and free) Aptana plugin has added support for AIR. You can now build your AIR HTML projects and do both compiling and packaging all from Eclipse.
It gets even better though. You can supply mutiple AIR SDK locations. So in the future when 1.1, or 1.5, or whatever, is released, you can work with both on your system.
You even get an option to include popular AJAX frameworks when creating your project. Unfortunately this doesn't the best one, Spry. (Ok, so maybe I'm biased.)