Flash specs are open sans the Sorenson codec which I don't think is that relevant - so anyone in theory could implement Flash without paying royalties.
But that's besides the point as no one will actually do it effectively - may be the spec is insane and it is impossible to make the pig fly.
But the real failure is not of Flash/Adobe - they went out and _did_ something to make the web richer and provide people with a tool to do what they want when progress on rich, dynamic, more capable standardized Web was painfully slow. The failure is of the Web Standards - I may be slightly off base but till this date HTML5 can't do half of what Flash is capable of doing. The only other alternative is Silverlight - not exactly better as it is less open and ubiquitous than Flash is.
[ On Linux : Using since '96 - But recently gave up on Linux as the Desktop. The latest I tried Flash on Fedora, it was screwed up because Flash gets memcpy wrong - overlapping - and some jerks decided to be uptight about it and fixed memcpy to break Flash. They may have their reasons and justifications but I no longer want to deal with that stuff anymore. Still contribute non-trivial patches to the kernel and manage a bunch of RHEL boxes - so still do Linux but just not on the Desktop.]
First, before May 1, 2008 the official specs for the swf format couldn't be used to create alternative implementations. If you read them, you were tainted. Even after, the spec didn't contain essential info like details about the RTMP protocol.
Second, it took an awful lot of time for Adobe to release specs, and the specs aren't really useful since devs from Gnash and SwfDec did a better job by reverse engineering, which is still legal.
And it can't help when Adobe is suing Wowza (as in, right now) or when it pulls rtmpdump from SourceForge with a DMCA request (May 26, 2009).
Third - open, as in public specs, doesn't mean it's a standard. It would be a standard if you were allowed not only to create an alternative implementation (debatable if you can) but if you were able to improve on it, improvements which may also be accepted in the standard.
And a real open standard requires a standards body, not a company that is willing to sue using patents whenever they feel like they aren't in control anymore.
If anything, the "opening" of those specs means absolutely nothing. Flash is still as closed as it was prior to May 2008. The only difference between now and then is the maturing of projects like Red5, but such projects are in a gray legal area. And THE alternatives to the official Flash client are still mostly unusable.
Go ask the Gnash or SwfDec developers about the openness of Flash.
But that's besides the point as no one will actually do it effectively - may be the spec is insane and it is impossible to make the pig fly.
But the real failure is not of Flash/Adobe - they went out and _did_ something to make the web richer and provide people with a tool to do what they want when progress on rich, dynamic, more capable standardized Web was painfully slow. The failure is of the Web Standards - I may be slightly off base but till this date HTML5 can't do half of what Flash is capable of doing. The only other alternative is Silverlight - not exactly better as it is less open and ubiquitous than Flash is.
[ On Linux : Using since '96 - But recently gave up on Linux as the Desktop. The latest I tried Flash on Fedora, it was screwed up because Flash gets memcpy wrong - overlapping - and some jerks decided to be uptight about it and fixed memcpy to break Flash. They may have their reasons and justifications but I no longer want to deal with that stuff anymore. Still contribute non-trivial patches to the kernel and manage a bunch of RHEL boxes - so still do Linux but just not on the Desktop.]