HTML5/Canvas
I’ve been playing with html5/canvas recently, and I do believe this will kill off Flash player eventually. It is still early though, and a lot of things are hard to do currently. I bet in a year though, there will be a ton of frameworks to make this much easier. Even Adobe with their ‘export to html5′ feature in CS5 knows this is coming.
One feature that is currently lacking in canvas is text rendering (fillText). It is just missing completely in Mobile Safari right now. And when it does work on desktop browsers, it doesn’t look so hot.
As for IE, I began my experiments using the explorer-canvas library (vml), but soon shifted to using fxcanvas (flash). Performance reasons drove me to do this, as well as it supporting more of the API. The project appears to be a bit more active, and even just today it has a new major release I need to try.
It may take awhile for more complex flash apps to migrate to html5, but for simpler things like charts & graphs, it seems to be a no-brainer to start converting.