You may want to check out Macromedia's site again. Flash MX is lightyears beyond the old Flash. This isn't your father's Flash.
Flash MX now supports OO coding and interfaces very nicely with Java, ASP, PHP, and .Net to enable the development of Rich Client Web applications (Rich Client functionality with virtually Zero footprint on the client machine).
Flash enhances PHP, ASP, Java, .Net etc. It doesn't just make things look pretty.
Flash has a dual personality:
Serious application developers can code in OO without using any of of Flash's animation tools.
Animators can still create incredible effects without coding (but the best do).
The GUI is just as important as the business logic created in PHP, etc. What good is a powerful business logic layer/tier if the user interface is cumbersome, slow or hard to use (e.g. the old mainframe interfaces of the 80's and the html interfaces of today).
Take another look at Flash.