I've been using Flash since version 3, so for me the arrival of 5 was a major event. My reaction when it arrived? At first, disappointment, but after using it for a while and getting used to its quirks, I have to say that going back to version 4 is now a real struggle.

The differences might initally seem cosmetic -- the interface has been 'panelised' and as such fits in better with Macromedia's other products (and will be a more comfortable environment for Adobe users). But the result isn't entirely comfortable -- there's a multitude of panels and options to contend with and it's not always an aid to workflow. You get used to it after a while, but some more thought should have gone into the way people will actually be using the interface.

The drawing tools really haven't changed (the bezier tool is of limited use) and certain features -- like improved masking and anti-alias options -- haven't been addressed at all.

The major changes come in the coding department. Actionscript, which in version 4 was a very limited, rather simplistic proprietary scripting language, has been completely revised and replaced with a ECMAScript-based (ie. similar to JavaScript) model. Some effort has been made to realise an object-oriented approach, but the result is a little haphazard -- at least partly, one assumes, to preserve backward-compatibility.

The new ActionScript is a massive improvement, though. With proper arrays and associated methods, improved maths functions, xml support and lots more, coding becomes a positive delight -- and you don't have to use that awful little dialogue box any more, either. The built-in editor has been vastly improved, or you cut and paste from an external editor if you prefer. The resulting code is far cleaner, more elegant and much easier to understand than before.

If you're worried about backwards compatibility while the new player is taken up then you can ex
port to Flash4, and it'll even let you know if you're trying to use incomaptible syntax.

The cherry on the cake is the useful, if somewhat temperamental, debugger. When it works (which is, sadly, rare) it is indispensable, allowing you to monitor the properties of movie clips, check variables and more, and all at run-time. Macromedia really needs to make it more stable, though.

Overall, an improvement over Flash 4 in most repsects, although perhaps not as great as it might have been.