Unless you're looking to do something pretty powerful you'll be fine with flash rather than shockwave, especially if you already know some ActionScript. (AS3 is somewhere between Javascript and Java for complexity depending on how you choose to use it)
Flash has better penetration and far more documentation/community support than Shockwave.
In terms of the dev environment, the above game was coded using eclipse to edit AS files and compiled through the Flash IDE, although you could use Flex to compile instead...
Unless you're looking to do something pretty powerful you'll be fine with flash rather than shockwave, especially if you already know some ActionScript. (AS3 is somewhere between Javascript and Java for complexity depending on how you choose to use it)
Flash has better penetration and far more documentation/community support than Shockwave.
In terms of the dev environment, the above game was coded using eclipse to edit AS files and compiled through the Flash IDE, although you could use Flex to compile instead...
Roll on flash 10 - UDP support!