I'm a flash developer and I'll be the first to admit that the format has some major drawbacks.
The parent is correct though, there are no viable alternatives to the format. Nothing I know of provides the kinds of experience that flash is capable is. (see this site
) Advertising drives the consumer side of the web and advertisers aren't going to move to less interactive or more static mediums. It also doesn't hurt that flash has a 99% penetration.
If there was a better platform with good penetration, while maintaining the ability to build rich interactivity, I'd be the first to jump.