Flash reached a point where it was basically unmaintainable spaghetti, and not something that was going to be trivially reimplemented by a third party. Sadly, that's exactly what's happening to the Web now. Instead of being standards-first, and browsers implement it, we've basically shifted to descriptive standards that attempt to formalize what a corporate cabal unilaterally decides. And we're in inch away from a homogeny of browser engines...
Well multilaterally decide. Its a small group but firefox isnt totally irrelavent yet.
And thats ok in my opinion. The IETF describes itself as "rough consensus and running code" and it seems to work well. I dont have a problem with the web following that model.