Recently I’ve been getting into a lot more AS3 development, the major hurdle for the projects I worked with and why they stuck their guns in AS2 was the fact most components we use were still AS2 based. This was a huge problem till I ran into this AS2-> AS3 bridge that allowed me to load AS2 swf’s into AS3 projects, works fantastically.
http://www.jumpeyecomponents.com/Flash-Components/Various/ActionScript-Bridge-91/