Open in what way? Open like GPL? Open like any company can suggest changes to the spec? Or just open enough that others can implement something just to have Adobe pull the rug out from underneath them? I'm sure if it was properly open, Mozilla or someone similar would jump at the chance to fix things, since the majority of Firefox crashes are due to Flash.

I liken Flash to the situation of a number of years back on the web when many sites required Internet Explorer. Other browsers were free to implement the broken and horrible behavior IE had in rendering the web, and I'm sure they could have supported ActiveX somehow. Thankfully that wasn't the way things went, and we now have a better web experience due to browsers shifting to proper open standards. Sure, back then it sucked to be forced into IE or just not see content, but eventually things changed and people got over it. The more non Flash platforms out there, the quicker the same thing will happen again, allowing people on mobile devices to finally see when a restaurant is open without some 5MB SWF download.