There have been a lot of exciting developments in Flash within the last couple years, especially with ActionScript3 (Flash CS3, Flex Builder), and because of these changes to the Flash “platform” the community has flourished. Open source projects are taking off and Flash finally has the functionality to facilitate real development (as opposed to all the fake development that has been done up til this point).
OSFlash is a good starting point for all the open source goodness.
If anyone is daunted by the prospects of learning Flash from ground zero, you should try to attend one of Colin Moock’s Adobe-sponsored ActionScript3 lectures or just get his book, Essential ActionScript 3.0.
There has always been exciting stuff happening on the Flash platform but there are all new possibilities,
such as real 3D, and a robust modern object-oriented environment. For some more examples what people are doing now, visit TheFWA.