Fellow Adobe Platform Evangelist Lee Brimelow has written an article for Adobe Developer Connection entitled Six reasons to use ActionScript 3.0. This one is a quick and useful read (the links at the bottom are very useful, too).
1. It is no different to C#, VB or Java.
2. Is it due to Flash Player and does Flash Player 9/10 makes only AS3 faster?
3. Who is using binary sockets on daily basis? Wasn’t AS2 using packages and imports?
4. Was swapDepths() really so hard to use?
5. I would not say AS3 is on the smae level as C#. That guy definitelly never used C# 3.5.
6. True – fun stays fun. Work is work.
After doing a few jobs in AS3, I reluctantly went back to AS2. There are some significant problems with AS3 — in particular, the memory usage problems and having to deal with all the different releases of the Flash 9 player, each with its own set of problems.
I would only consider using AS3 if I could specify release 115 as the minimum version. I see this release is now installed on over 80% of computers, so maybe…but I’m inclined to wait for a couple of inevitable bug fixes in the Flash 10 player before completely switching over to AS3.
I love AS3 I admit i still use AS2 on occasion however i use it very little anymore. I know some of our designers liked AS2 better but we created an extension panel that allows them to simply use either. I think if you give it some time you will see why so many of the top designers like it so much!!