just got it in the mail yesterday. for those that don't know much about it, it's macromedia's newest wysiwyg for standards-based programming. it still uses the same familiar programming methodology and workflow as dreamweaver but includes a more powerful class library. i haven't installed it yet so i can't give any details on its interface or usability and functionality, but i'm looking forward to trying it out.
you can get more info here: http://www.macromedia.com/software/flex/
if anyone has any comments you are welcome to share as i am still learning standards-based programming.