The main reason I don't and never used flash is because the entire stack is mostly proprietary. Developing for it required tools from Macromedia/Adobe (At leas

The main reason I don't and never used flash is because the entire stack is mostly proprietary. Developing for it required tools from Macromedia/Adobe (At least, I never found a decent open variant). Flash applications also tended to have poorly integrated user interfaces. All of the standard web-browing features (back, forward, copy link location, save image, open link in new window, etc.) had to be replicated by the developer of each individual application. So most of them functioned poorly. And CPU utilization was not the metric people used against flash with regard to performance complaints. The metric was time spent waiting for the goddamn site to load. People complained about flash's performance in two main scenarios. The first, were sites that were supposed to be useful that tried to be overly creative with intro movies and fancy dynamic menus that users had to wait for. The second scenario was pages with flash-based ads, where once again, content on the page would take longer to display because the browser was busy downloading and running banner ads that were 100x the size and complexity of the target content.